Why, as of yesterday, are we getting involved militarily?

I am strongly opposed to the U.S. inserting itself into yet another conflict where, despite assurances of limited engagement, there is certainly a chance of escalation and a decade's worth of fighting and/or peacekeeping...when we haven't wrapped up two other major drawn-out conflicts/nation-building exercises.

There are so many questions: Why now and not earlier in the civil war?  Why this country and not many others where people are oppressed by their leaders?  Is this about our national interest in any way (even if this was about resources, 85% of Libya's oil is exported to Europe)?  Did the President request a declaration of war from Congress before authorizing U.S. engagement - when it was clearly possible?  And what other diplomatic efforts did the U.S. actually undertake before this step - since Obama said “I want the American people to know that the use of force is not our first choice, and it’s not a choice that I make lightly." - ?  How are we paying for the expenditures that accompany the many cruise missiles fired, etc.?

There is also the grim irony that Drudge points out rather effectively:

MARCH 19, 2011
OBAMA: 'Today we are part of a broad coalition. We are answering the calls of a threatened people. And we are acting in the interests of the United States and the world'...

MARCH 19, 2003
BUSH: 'American and coalition forces are in the early stages of military operations to disarm Iraq, to free its people and to defend the world from grave danger'...

Yes, there is support coming from various European quarters.  Yes, the UN Security Council authorized the action.  Yes, one could hope that this exercise will resemble the first Gulf War rather than the conflicts in Afghanistan and Iraq.  Yes, a despot is acting brutally against his own people.

But I don't think this is a matter worth engaging in at this time, as far as the U.S. is concerned.