It should be obvious: border security is hostage to amnesty for illegals.

"The sad and shameful truth is that Obama's lawsuit against Arizona’s tough new immigration law is part of a grand scheme to ram Amnesty for millions of illegal aliens down the throats of the American people."
***Why is this so important to Obama and the Democrats? They believe that illegal immigrants will be a dominating voting bloc for Democrats. Just as they count on the felon vote ( >1000 illegal votes by felons in Minnesota provided the margin of victory for Al Franken who won by 350 votes in a progressively narrowing series of recounts.) Obama admitted that he won't secure the border because that would relieve pressure for a "comprehensive" immigration bill. Why comprehensive? Because the goal is to get the vote for all the illegals. Why is this good for America? It isn't. We would be making citizens out of lawbreakers who provide lower-than-average contributions to the GDP. The only feature Obama likes is that they're likely to vote Democratic.***