As the boss put it in Headlines this morning, “hell freezes over.” Proverb or no proverb, I’m looking this gift horse right in the mouth. What’s The One’s game here?

“We mean this, we’re serious about it, and we believe we need to put in an all-out effort to get this done,” said Rep. David E. Price (D-N.C.), chairman of the House Appropriations subcommittee for homeland security. He has led calls to remove illegal immigrants convicted of crimes after their sentences are served…

Under the new program, the immigration checks will be automatic: Fingerprints currently being run through the FBI’s criminal history database also will be matched against immigration databases maintained by the Department of Homeland Security. The effort would not catch people who have never been fingerprinted by U.S. authorities.

Based on the pilot program, the agency estimates that if fingerprints from all 14 million bookings in local jails each year were screened, about 1.4 million “criminal aliens” would be found, Venturella said. That would be about 10 times the 117,000 criminal illegal immigrants ICE deported last year. There are more than 3,100 local jails nationwide, compared with about 1,200 federal and state prisons…

In his proposed 2010 budget, President Obama asked Congress last week for $200 million for the program, a 30 percent increase that puts it on track to receive $1.1 billion by 2013…

Amnesty International and immigrant advocates warn that the change could lead to immigration checks in other arenas and the “criminalization” of illegal immigration.

So alarmingly sensible does this sound that I’m panicked at what the catch might be. Trawl the Hot Air archives (or Michelle’s archives, needless to say) for “criminal illegal aliens” and you’ll turn up dozens of posts about the human toll from illegals who commit crimes, do their time, and then are merrily released back onto the streets without prison officials so much as once checking their status. Patterico had a running series about this phenomenon a few years ago before he gave up, presumably from the sheer volume of incidents he’d have to cover to keep it going. Heather MacDonald’s written about it at length at City Journal too. I can only assume this is The One’s concession to conservatives and centrist Democrats as a prelude to the big amnesty push he’s planning as soon as the economy starts to recover, but even viewed in that context, I’d never have expected him to do something this … rational. And ironically, probably the only reason he feels safe in doing it is because the GOP’s standing with Latinos has sunk so low that Obama doesn’t have to worry about losing too many votes because of it. (Although he will lose some: Last time I looked, our pal Geraldo opposed checking the immigration status of criminals convicted of anything less than a Class A felony.) Exit question: What’s the catch here?