                 FOR PUBLICATION
 UNITED STATES COURT OF APPEALS
      FOR THE NINTH CIRCUIT

UNITED STATES OF AMERICA,                  No. 07-50239
                Plaintiff-Appellee,
               v.                            D.C. No.
                                          CR-06-02104-WQH
JAVIER AMEZCUA-VASQUEZ,
                                              OPINION
             Defendant-Appellant.
                                      
       Appeal from the United States District Court
         for the Southern District of California
       William Q. Hayes, District Judge, Presiding

                  Argued and Submitted
           April 10, 2008—Pasadena, California

                    Filed June 1, 2009

  Before: William C. Canby, Jr., Andrew J. Kleinfeld, and
               Jay S. Bybee, Circuit Judges.

                 Opinion by Judge Canby




                           6523
6526         UNITED STATES v. AMEZCUA-VASQUEZ




                       COUNSEL

Janet C. Tung, Federal Defenders of San Diego, Inc., San
Diego, California, for the defendant-appellant.

Christopher M. Alexander, Assistant United States Attorney,
San Diego, California, for the plaintiff-appellee.
              UNITED STATES v. AMEZCUA-VASQUEZ             6527
                          OPINION

CANBY, Circuit Judge:

                        OVERVIEW

   Javier Amezcua-Vasquez (“Amezcua”), a native and citi-
zen of Mexico, appeals his 52-month prison sentence for
attempting to reenter the United States unlawfully in violation
of 8 U.S.C. § 1326. Nearly fifty years after becoming a per-
manent resident and more than twenty years after completing
a four-year sentence for assault with great bodily injury and
attempted voluntary manslaughter, Amezcua was deported to
Mexico as an alien convicted of an aggravated felony. Shortly
thereafter, he was apprehended re-entering the United States.
He was indicted and pled guilty to one count of illegal reentry
in violation of 8 U.S.C. § 1326. The district court applied a
16-level enhancement under U.S.S.G. § 2L1.2(b)(1)(A)(ii),
which was predicated on Amezcua’s twenty-five-year-old
convictions, and imposed a Guidelines sentence of 52 months
imprisonment. We vacate Amezcua’s sentence as substan-
tively unreasonable under United States v. Booker, 543 U.S.
220 (2005), and remand the case to the district court for resen-
tencing.

                      BACKGROUND

   In 1957, Amezcua, a native and citizen of Mexico, became
a permanent resident of the United States. He was two years
old at the time. He has lived in or around Calipatria, Califor-
nia, ever since. In 1981, at the age of twenty-six, Amezcua
stabbed someone with a knife in the midst of a gang-related
bar fight. As a result, he was convicted in state court of
attempted voluntary manslaughter and assault with great bod-
ily injury. He was sentenced to concurrent terms of eight
months on the attempted manslaughter count and four years
on the assault count. Amezcua’s sentence was initially sus-
pended, but his probation was revoked in 1982. He was
6528          UNITED STATES v. AMEZCUA-VASQUEZ
released on parole in 1984 and was discharged the following
year. In 2006, at the age of fifty-one, Amezcua was ordered
removed to Mexico as an alien convicted of an aggravated fel-
ony because of his 1981 convictions.

   Two weeks after his removal, Amezcua was apprehended
entering the United States in the vicinity of Calexico, Califor-
nia. After waving his Miranda and Vienna Convention rights,
Amezcua admitted that he was not a United States citizen and
that he was unlawfully in the United States after having been
deported. He informed the agents that he had been staying in
Mexicali, Mexico, since his deportation two weeks earlier and
that, at the time of his arrest, he was attempting to return to
El Centro, California, to live with his family and work.

   A few months later, Amezcua was indicted on one count of
attempted illegal reentry in violation of 8 U.S.C. § 1326(a)-
(b). He pled guilty without a plea agreement. The district
judge adopted the following offense level computation in the
Presentence Report:

    Base Offense Level: 8 U.S.C. § 1326                8

    Specific Offense Characteristics:
    U.S.S.G. § 2L1.2(b)(1)(A)(ii)                      16

    Adjusted Offense Level:

    Adjustment for Acceptance of Responsibility:       -2

    Total Offense Level:                               22

With respect to his criminal history, the only conviction that
qualified under Chapter IV of the Guidelines was a 1999 con-
viction for “us[ing], or be[ing] under the influence of any con-
trolled substance,” Cal. Health & Safety Code § 11550(a),
which placed Amezcua in category II. Amezcua’s other con-
victions, including the 1981 conviction, did not score under
                 UNITED STATES v. AMEZCUA-VASQUEZ                     6529
the Guidelines because they were too old.1 U.S.S.G.
§ 4A1.2(e). Similarly, Amezcua’s law enforcement contacts
did not score under the Guidelines.2

   At sentencing, the judge stated that he had read Amezcua’s
sentencing memorandum and the Presentence Report, which
discussed Amezcua’s background. The Report noted Amez-
cua’s extensive family network around El Centro, California,
his absence from Mexico since he was two years old, his work
experience as an agricultural worker in the fields of California
and as a handyman in the community, and his history of alco-
hol and drug abuse. The district judge determined that the
Guidelines range for a defendant with Amezcua’s offense
level (22) and criminal history category (II) was 46 to 57
months, followed by a term of 2 to 3 years under supervised
release. Amezcua objected to the application of the 16-level
enhancement under U.S.S.G. § 2L1.2(b)(1)(A)(ii) on the
ground that neither of his 1981 convictions qualified as a
“crime of violence.” He also challenged the reasonableness of
the proposed Guidelines sentence in light of his personal his-
tory and characteristics.

   At sentencing, the district judge noted that the Guidelines
are merely advisory and that Amezcua’s 1981 conviction
qualified as a crime of violence under Sec-
tion 2L1.2(b)(1)(A)(ii).     After   discussing     Amezcua’s
uncharged law enforcement contacts and his prior convic-
tions, and the statutory sentencing factors under 18 U.S.C.
§ 3553(a), the district judge imposed a sentence of 52 months
imprisonment, followed by three years of supervised release.
Amezcua appeals.
  1
     Amezcua’s other convictions were for reckless driving (1974), drunk
driving (1978), resisting a police officer (1978), battery (1987), violation
of a court order (1993) and driving under the influence (1993).
   2
     Amezcua’s law enforcement contacts have been for use of a controlled
substance. They have not involved trafficking.
6530           UNITED STATES v. AMEZCUA-VASQUEZ
                          DISCUSSION

   Our “appellate review of sentencing decisions is limited to
determining whether they are ‘reasonable.’ ” Gall v. United
States, 128 S. Ct. 586, 594 (2007). In conducting this inquiry,
we review the district court’s sentencing decision for an abuse
of discretion. Id. at 600. “[O]nly a procedurally erroneous or
substantively unreasonable sentence will be set aside.” United
States v. Carty, 520 F.3d 984, 993 (9th Cir. 2008) (en banc).
“[W]e first consider whether the district court committed sig-
nificant procedural error, then we consider the substantive
reasonableness of the sentence.” Id. (citing Gall, 128 S. Ct. at
597).

  Procedural Reasonableness

   [1] In his only procedural challenge,3 Amezcua contends
that the district court failed properly to consider and discuss
his arguments for lenient sentencing that cast his personal his-
tory in a positive light. Although the district court’s treatment
of these arguments was brief, we find no procedural error.
Under the sentencing statute, the district court was required to
“state in open court the reasons for its imposition of the [52-
month] sentence.” 18 U.S.C. § 3553(c). As the Supreme Court
has recently announced, however, this obligation does “not
necessarily require lengthy explanation.” Rita v. United
States, 127 S. Ct. 2456, 2468 (2007). “Circumstances may
well make clear that the judge rests his decision upon the
Commission’s own reasoning that the Guidelines sentence is
a proper sentence (in terms of § 3553(a) and other congressio-
nal mandates) in the typical case, and that the judge has found
that the case before him is typical.” Id. Accordingly, although
it is the better practice for district courts to explain whether
they accept or reject “nonfrivolous argument[s] tethered to a
  3
   On this appeal, Amezcua no longer argues—as he did in the district
court—that his 1981 convictions do not constitute “crimes of violence”
within the meaning of U.S.S.G. § 2L1.2(b)(1)(A)(ii).
              UNITED STATES v. AMEZCUA-VASQUEZ                6531
relevant § 3553(a) factor,” Carty, 520 F.3d at 992-93, a sen-
tencing judge does not abuse his discretion when he listens to
the defendant’s arguments and then “simply [finds the] cir-
cumstances insufficient to warrant a sentence lower than the
Guidelines range,” id. at 995 (quoting Rita, 127 S.Ct. at
2469); see also United States v. Stoterau, 524 F.3d 988, 999
(9th Cir. 2008).

   In this case, the district court began its analysis of the sen-
tencing factors by noting that two of the arguments discussed
in connection with the computation of the advisory Guidelines
range—that is, “the nature and circumstances of the offense
and [the] history and characteristics of the defendant”—were
also relevant to its § 3553(a) inquiry. It then stated:

    With respect to the 3553 factors, I have considered
    all of them. Some in particular I’ll mention. In addi-
    tion to the nature and circumstances of the offense,
    the need to reflect the seriousness of the offense,
    promote respect for law, and to provide just punish-
    ment for the offense, as well as to afford adequate
    deterrence to criminal conduct, and having closely
    examined the defendant’s prior record and the cir-
    cumstances of the offense, the Court is going to
    impose a sentence in the amount of 52 months.

This explanation effectively singled out the factors enumer-
ated in subsections (a)(1), (a)(2)(A) and (a)(2)(B) of 18
U.S.C. § 3553 as particularly relevant to the district court’s
sentencing decision in this case. Turning to the specifics of
Amezcua’s case, the district court continued:

       I think that [a 52-month sentence] is the minimum
    sentence that would afford deterrence to criminal
    conduct. I recognize that the facts of this offense are
    not particularly aggravating, but that the defendant’s
    prior criminal history and contacts with law enforce-
    ment, he’s had some significant contacts . . . .
6532          UNITED STATES v. AMEZCUA-VASQUEZ
       Under 3553 factors, I think that the 52-month sen-
    tence is necessary to promote respect for the law and
    provide just punishment, and I also believe that that
    is a sentence that is necessary in order to avoid
    unwarranted sentencing disparities among defen-
    dants with similar records who have been found
    guilty of similar conduct, and I don’t think that a
    sentence of less than 52 months would satisfy the
    3553 factors.

   [2] We conclude that this discussion of the § 3553(a) fac-
tors sufficed. We recognize that, at the sentencing hearing, the
district court did not mention several of Amezcua’s mitigating
arguments pertaining to his “history and characteristics.” 18
U.S.C. 3553(a)(1). We also recognize that some of these argu-
ments were undoubtedly weighty—in particular, Amezcua’s
cultural assimilation resulting from spending his entire life
after the age of two years in the United States and his under-
standable difficulty in adjusting to life in Mexico after living
in the United States for half a century. On the record as a
whole, however, we are satisfied that the court “listened to
[Amezcua]’s argument[s]” and “then simply found these cir-
cumstances insufficient to warrant a sentence lower than the
Guidelines range.” Rita, 127 S. Ct. at 2469. Nothing more
was required to comply with the procedural mandate articu-
lated in Rita.

  Substantive Reasonableness

   In his principal challenge to the substantive reasonableness
of his sentence, Amezcua contends that the sentence imposed
by the district court is unreasonable because it is the product
of a 16-level enhancement under U.S.S.G. § 2L1.2(b)(1)(A),
which is predicated on a conviction that is too old to score
under the Guidelines’ criminal history provisions. See
U.S.S.G. § 4A1.2(e). It is not per se unreasonable to apply the
enhancement when the conviction is too stale to be counted
for purposes of the criminal history. See Lara-Aceves, 183
              UNITED STATES v. AMEZCUA-VASQUEZ               6533
F.3d 1007, 1013-14 (9th Cir. 1999), overruled on other
grounds by United States v. Rivera-Sanchez, 247 F.3d 905,
909 (9th Cir. 2001) (en banc). We conclude, however, that
under the circumstances of this case, it was unreasonable to
adhere to the Guidelines sentence, with its full 16-level
enhancement under § 2L1.2(b), because of the staleness of
Amezcua’s prior conviction and his subsequent history show-
ing no convictions for harming others or committing other
crimes listed in Section 2L1.2. We therefore vacate Amez-
cua’s sentence, and remand for resentencing.

   [3] In determining the substantive reasonableness of Amez-
cua’s 52-month sentence, we “consider the totality of the cir-
cumstances” and attach no presumption of reasonableness to
the fact that Amezcua’s sentence falls within the applicable
Guidelines range. Carty, 520 F.3d at 993 (citing Gall, 128
S. Ct. at 597). We are mindful, however, that “a Guidelines
sentence ‘will usually be reasonable,’ ” id. at 994 (quoting
Rita, 127 S. Ct. at 2465), for “[a]n individual judge who
imposes a sentence within the range recommended by the
Guidelines thus makes a decision that is fully consistent with
the Commission’s judgment in general.” Rita, 127 S. Ct. at
2465. We review the sentencing decision for abuse of discre-
tion, and “[t]he fact that [we] might reasonably [conclude]
that a different sentence [is] appropriate is insufficient to jus-
tify reversal of the district court.” Gall, 128 S. Ct. at 597.
Nevertheless, we may reverse if, upon reviewing the record,
we have a definite and firm conviction that the district court
committed a clear error of judgment in the conclusion it
reached upon weighing the relevant factors.

   [4] After giving due weight to these principles, we con-
clude that Amezcua’s Guidelines sentence “fails properly to
reflect § 3553(a) considerations.” Rita, 127 S. Ct. at 2465. On
the facts of this case, the unmitigated application of the
Guidelines sentence with its 16-level enhancement under
U.S.S.G. § 2L1.2(b)(1)(A) substantially overstates “the nature
and circumstances of [Amezcua’s] offense [and] . . . the need
6534           UNITED STATES v. AMEZCUA-VASQUEZ
for the sentence imposed . . . to reflect the seriousness of the
offense, to promote respect for the law, and to provide just
punishment for the offense.” 18 U.S.C. § 3553(a)(1)-(2)(A).
Section 2L1.2(b)(1)(A)(ii) requires a 16-level, 200 percent
increase from the base offense level if the defendant “previ-
ously was deported . . . after . . . a conviction for a felony that
is . . . a crime of violence.” U.S.S.G. § 2L1.2(a)-(b). The
enhancement applies regardless of the time of conviction. See
U.S.S.G. § 2L1.2 app. note 1(B)(vii). That is so because Sec-
tion 2L1.2(b) “ ‘is a measure of the seriousness of the crime
committed, ratcheting up the sentence because it is a more
serious offense to return after deportation when the defendant
has previously committed a serious crime—an aggravated fel-
ony.’ ” United States v. Lara-Aceves, 183 F.3d at 1014 (quot-
ing United States v. Gonzalez-Mendez, 112 F.3d 1325, 1329
(7th Cir. 1997)).

   [5] The crucial question, then, is whether the measure of
seriousness provided by the 16-level enhancement is in fact
reasonable. We conclude that, on the facts of this case, it is
not. The fact that Section 2L1.2(b) addresses the seriousness
of the offense—as opposed to the risk of recidivism—
explains the absence of time limitations on qualifying predi-
cate convictions. See U.S.S.G. § 2L1.2 app. note 1(B)(vii);
Lara-Aceves, 183 F.3d at 1014. It does not, however, justify
increasing a defendant’s sentence by the same magnitude irre-
spective of the age of the prior conviction at the time of reen-
try. Although it may be reasonable to take some account of an
aggravated felony, no matter how stale, in assessing the seri-
ousness of an unlawful reentry into the country, it does not
follow that it is inevitably reasonable to assume that a
decades-old prior conviction is deserving of the same severe
additional punishment as a recent one. The staleness of the
conviction does not affect the Guidelines calculation, but it
does affect the § 3553(a) analysis. We hold that the district
court abused its discretion when it applied the Guidelines sen-
tence to Amezcua without making allowances for the stale-
ness of the prior conviction and his subsequent lack of any
                 UNITED STATES v. AMEZCUA-VASQUEZ                     6535
other convictions for violent crimes. The result was an unrea-
sonable sentence.

   [6] This is a case where the Guidelines calculation, includ-
ing the 16-level enhancement, was correct, but the age of the
conviction and the circumstances of this individual neverthe-
less require a variance under § 3553(a) from a Guidelines sen-
tence. Amezcua was convicted of assault with great bodily
injury and attempted voluntary manslaughter in 1981, twenty-
five years prior to his removal to Mexico and subsequent
unlawful reentry. He was sentenced to four years in prison at
the time and was released in 1984. Neither of his convictions
even qualified as “aggravated felonies” under Title 8 until 1996.4
Finally, although he has evidently struggled with a substance
addiction, there is no indication that he has committed another
offense listed in Section 2L1.2 or has harmed or attempted to
harm another person or the property of another for the past
twenty years. Because his 1984 convictions were very old and
unrepresentative of Amezcua’s characteristics during the past
many years, we conclude that the Guidelines calculation
yielded a sentence exceeding what was reasonable under
§ 3553(a). Section 2L1.2 is designed to measure “the serious-
ness of the crime committed,” where the crime is “return[ing]
   4
     In 1990, Congress expanded the definition of “aggravated felony” to
include “crime[s] of violence . . . for which the term of imprisonment
imposed (regardless of any suspension of such imprisonment) is at least
5 years.” Immigration Act of 1990, Pub. L. No. 101-649, § 501(a)(3), 104
Stat. 4978, 5048 (1990). Amezcua’s 1981 convictions did not qualify
under this definition because he was sentenced to four years. Moreover,
the amendment applied only prospectively. Id. § 501(b). In 1996, Con-
gress enacted the Illegal Immigration Reform and Immigrant Responsibil-
ity Act, which further extended the definition of “aggravated felony” to
include crimes of violence “for which the term of imprisonment [is] at
least one year.” Pub. L. No. 104-208, Div. C, §§ 321(a)(3), 322(a)(2)(A),
110 Stat. 3009-546, 3009-627 (1996). The 1996 amendment applied “re-
gardless of whether the conviction was entered before, on, or after the date
of enactment.” Id. § 321(b). It was at this point that Amezcua’s convic-
tions first qualified as “aggravated felonies” under Title 8. 8 U.S.C.
§ 1101(a)(43).
6536          UNITED STATES v. AMEZCUA-VASQUEZ
after deportation when the defendant has previously commit-
ted a serious crime.” Lara-Aceves, 183 F.3d at 1014. Even
under this definition, there is no doubt that Amezcua’s illegal
return after having committed an offense listed in Section
2L1.2 over 20 years earlier, after which he was never con-
victed again of any such listed crime or of harming another
person, is a significantly less “serious crime committed” than
an illegal return very soon after having committed a serious
crime. The district court abused its discretion by failing to
measure the seriousness of Amezcua’s particular offense
when applying Section 2L1.2 and to vary from the Guidelines
sentence accordingly.

   Our decision today is not inconsistent with the rationale of
two of our recent post-Carty decisions: United States v.
Whitehead, 532 F.3d 991 (9th Cir. 2008) (per curiam); United
States v. Ruff, 535 F.3d 999 (9th Cir. 2008). In those cases,
we upheld as reasonable non-Guidelines sentences that
involved minimal, if any, prison time notwithstanding advi-
sory Guidelines ranges of 41 to 51 months and 30 to 37
months, respectively. In doing so, we emphasized the broad
discretion enjoyed by district courts in fashioning sentences
that fully and adequately reflect the penological factors set
forth in 18 U.S.C. § 3553(a). Whitehead, 532 F.3d at 993;
Ruff, 532 F.3d at 1003-04.

   These cases are analytically distinguishable from the pres-
ent appeal, however. Unlike the sentences imposed in those
cases, the sentence at issue in this appeal is not the product
of defendant-specific § 3553(a) mitigating (or aggravating)
factors with respect to which “the district court was ‘in a
superior position’ to find the relevant facts and to ‘judge their
import.’ ” Whitehead, 532 F.3d at 993 (quoting Gall, 128
S. Ct. at 597); see also Ruff, 535 F.3d at 1004. In this case the
district court did not deviate from the Guidelines by applying
defendant-specific factors that it was in a superior position to
adjudge. On the contrary, the district court applied the Guide-
lines sentence without considering the defendant-specific
                 UNITED STATES v. AMEZCUA-VASQUEZ                      6537
facts that made the resulting sentence unreasonable under
§ 3553(a)—i.e., the staleness of the predicate prior conviction
and its diminished import on the severity of the illegal reentry
decades after the original conviction.5 Neither Whitehead nor
Ruff requires us to affirm the sentence in the present circum-
stances.

   Having concluded that the Guidelines sentencing range in
this case unreasonably overstates the offense-specific sentenc-
ing factors, 18 U.S.C. § 3553(a)(1)-(2)(A), we must still con-
sider whether the ultimate sentence may nonetheless be
justified in light of other aggravating sentencing consider-
ations. The district court identified two such considerations
that are relevant to this case: the need to “afford adequate
deterrence to criminal conduct,” id. § 3553(a)(2)(B), and “the
need to avoid unwarranted sentence disparities among defen-
dants with similar records who have been found guilty of sim-
ilar conduct,” id. § 3553(a)(6). Neither of these factors,
   5
     We note that the Supreme Court has vacated in light of Gall and
remanded for re-sentencing a number of illegal reentry cases where the
defendants were given Guideline sentences that included violent crime
enhancements. See Rodriguez-Rodriguez v. United States, 128 S. Ct. 876
(2008) (vacating affirmance of a 57-month Guidelines sentence for violat-
ing 8 U.S.C. § 1326 and remanding for further consideration in light of
Gall), aff’d on remand sub nom. United States v. Rodriguez-Rodriguez,
530 F.3d 381 (5th Cir. 2008); Jaimes-Aguirre v. United States, 128 S. Ct.
2934 (2008) (vacating affirmance of an enhanced Guidelines sentence for
violating 8 U.S.C. § 1326 and remanding for further consideration in light
of Gall); Salazar-Garcia v. United States, 128 S. Ct. 2934 (2008) (vacat-
ing affirmance of a 70-month Guidelines sentence for violating 8 U.S.C.
§ 1326 and remanding for further consideration in light of Gall);
Alvarado-Molina v. United States, 128 S. Ct. 2425 (2008) (vacating affir-
mance of a 46-month Guidelines sentence for violating 8 U.S.C. § 1326
and remanding for further consideration in light of Gall), reaff’d on
remand sub nom. United States v. Alvarado-Molina, 288 Fed. Appx. 448
(10th Cir. 2008) (mem.). Although we must not read too much meaning
into these bare orders, they support the view that, at least in some applica-
tions, the Guidelines prior crime enhancements can lead to unreasonable
sentences.
6538          UNITED STATES v. AMEZCUA-VASQUEZ
whether considered in isolation or in the aggregate, justifies
a 52-month sentence.

   In its discussion of deterrence, the district court correctly
pointed to certain prior convictions, including the 1981 con-
victions, which are too old to affect Amezcua’s criminal his-
tory score under the Guidelines. It also pointed to other more
recent non-scoring law enforcement contacts for substance
abuse. It is unreasonable, though, to treat a decades-old
enhancing conviction as requiring as much deterrence as a
recent conviction. Finally, “the need to avoid unwarranted
sentence disparities” among similarly situated defendants
does not weigh against Amezcua. 18 U.S.C. § 3553(a)(6).
While it is important to avoid “unwarranted sentence dispari-
ties among defendants with similar records who have been
found guilty of similar conduct,” 18 U.S.C. § 3553(a)(6), it is
also legitimate to avoid “unwarranted similarities among
[defendants] who were not similarly situated.” Gall, 128
S. Ct. at 600 (emphasis in original). It is not reasonable for
Amezcua’s record of relative harmlessness to others for the
past twenty years to subject him to the same severe offense
level enhancement applied to a recent violent offender.

                             ***

   [7] The scope of our decision is limited. We hold that, on
the specific set of facts presented by this case, a 52-month
sentence that is largely predetermined by a 16-level enhance-
ment under U.S.S.G. § 2L1.2(b)(1)(A) is substantively unrea-
sonable, and it was an abuse of discretion for the district court
to impose it. We make no pronouncement as to the reason-
ableness of a comparable sentence were Amezcua’s convic-
tion more recent, the sentence resulting from the prior
conviction more severe or “the need . . . to protect the public
from further crimes of the defendant” otherwise greater. 18
U.S.C. § 3553(a)(2)(C).
            UNITED STATES v. AMEZCUA-VASQUEZ       6539
                    CONCLUSION

  We vacate Amezcua’s sentence and remand for resentenc-
ing consistent with this opinion.

 SENTENCE VACATED; REMANDED FOR RESEN-
TENCING.
