Legalising Those Here Illegally Is What A Certain Kind Of Conservative Calls Amnesty

For a certain kind of conservative, any attempt to grant a legal status to illegal immigrants is as welcome as salsa on their apple pie. ~Michael Gerson

Is there some reason why granting legal status to illegal immigrants should be received any more enthusiastically?  Also, salsa-on-apple-pie is just about as clumsy and blunt a metaphor as it gets.  The only worse way to say what Gerson means to say about these people (“these people don’t like Mexicans”) would be to talk about a tequilla-soaked flag.  This guy was a speechwriter?  For the President?