Heh....pretty good DT...
There are elections in November, and the Obama Administration is keenly aware of campaign promises - which if not kept can work against him in November:
he had promised upon winning the White House is being delivered
(Googled from this source: http://www.reuters.com/article/idUSTRE59E0Q920091015
Also this citation contains a video-link to a Lou Dobbs report containing footage of Obama's actual announcement, which is fairly alarming in tone:
On the other hand, the report indicates that Obama made his remarks upon returning from Mexico, where Obama is under pressure from the Mexican Administration to support Calderon in his war against narco-trafficking (and weapons trafficking). Calderon is not happy
with the U.S. - see: http://www.commondreams.org/headline/2010/03/28-7
Gun control disguised as foreign policy, and particularly as support for promises made during his past campaign (to support his position vis a vis the November elections).
Still, the fact is that it is by no means a done deal, and there would be tremendous resistance to this not only in the Senate and House, but amongst voters as well.