For some, this may seem like picking a nit.  But Barack Obama's statement from Brazil over the weekend justifying American action against Libya on the grounds that "we [the United States] can't stand idly by when a tyrant tells his people that there will be no mercy" seems like shaky grounds for American military intervention.     

Are we to assume that if Muammar Qaddafi had said nothing but went about slaughtering innocents, the President would have chosen not to act?  But assuming that the President's statement was poorly constructed, and that he meant that American military intervention was necessitated by the murder of Libyan innocents, then in a world full of despots who routinely murder innocents, where won't the United States intervene?

Are we to assume that there's a threshold that a tyrant needs to meet in killing innocents before the United States steps in (with the approval of the United Nations and in full concert with American allies, of course)?  What would that threshold be?  Ten, a hundred, a thousand, ten thousand dead? 

Should the United States and its allies take action against Iran's mullahs, who undoubtedly kill innocents?  Or Syria?  Perhaps there's still something Mr. Obama can do in Darfur?  And the President might as well check out Cuba; Fidel Castro has quite a record of murdering innocents, and still may be doing so.

Humanitarian considerations cannot be lightly dismissed.  But in the hard world of international affairs, its national self-interest that needs to be the guiding standard for a nation's military actions.  The United States is no exception. 

If Libya merits American military action, then the President needs to justify that action based on concrete arguments of national self-interest, not fuzzy "We are the World" tripe.

The cynic may argue that Barack Obama may be pursuing some tangible, vital American interest by intervening in Libya, but that the President needs to mask his intention to protect his exposed left flank.  Liberals, you see, find military action for national self-interest, well, not abstract enough and not feel-good enough. 

Americans, in the main, tend not to want their soldiers put in harm's way or their tax dollars spent in vain attempts to save the world from itself.  It's ultimately a losing proposition. 

Congressional Republicans, while rightly denouncing Qaddafi for his inhumanity, need to demand that the President explain to Congress and the American people what direct national interest is served by United States military intervention in Libya, no matter how "limited" that intervention is claimed to be in scope and duration.

Disagree with George W. Bush's decisions, but he had solid reasons based on American national security considerations for fighting wars in Iraq and Afghanistan. 

Barack Obama needs to produce reasons why American treasure and, perhaps, blood are being spent in Libya.