Peter Beinart, in a piece about Joseph Lieberman in the New Republic, nicely adumbrates what might be termed the "hawks' dilemma" - the dilemma of liberal hawks, that is. Of course, not all "liberal hawks" (I use that unsatisfactory formulation for convenience's sake) find themselves in the predicament Beinart describes, but I'm sure we'd all at least recognise it:
Behind Lieberman's obsession with national unity is his deep conviction that the United States is at war--not just in Iraq, but around the world. The war on terrorism is his prism for viewing Bush. And it drains away his anger at the president's misdeeds, because they always pale in comparison to those of America's true enemy.
According to Beinart, what Lieberman lacks -and I think the point applies quite widely- is a sense of what Irving Howe called "two-sided politics":
Liberals are engaged in two different struggles--one against illiberalism at home, the other against an even more profound illiberalism abroad. Both must be fought with passion. Neither can be subsumed. Each must be sometimes compromised for the sake of the other. It is that moral tension--more than Bush-hatred, and more than wartime unity--that defines the liberal spirit.