text: but as an initial matter,congress may have had good reason to think that a statutory reference would capture more accurately than a generic label the range of state convictions warranting automatic deportation.the clause of a applying to luna case well illustrates the point.by referring to i,that provision incorporates not only the arson offenses that a generic arson label would cover,but various explosives offenses too.see brief for petitioner,conceding that had congress used the term arson,it would have had to separately identify the explosives crimes encompassed in i.and the elements of generic arson are themselves so uncertain as to pose problems for a court having to decide whether they are present in a given state law.see poulos,the metamorphosis of the law of arson,describing multiple conflicts over what conduct the term arson includes.nor is the clause at issue here unusual in those respects section a includes many other statutory references that do not convert easily to generic labels.see,a e ii listing federal statutes defining various firearms offenses.to be sure,congress used such labels to describe some crimes qualifying as aggravated felonies for example,murder,rape,or sexual abuse of a minor.a a.but what is good for some crimes is not for others.the use of a federal statutory reference shows only that congress thought it the best way to identify certain substantive crimes not that congress wanted in conflict with the penultimate sentence to exclude state and foreign versions of those offenses for lack of a jurisdictional element.