Second, even assuming that Libya is an important "adventure" and conceding that multilateral action may be preferable, multilateralism is not worthwhile when it delays action, which if taken quickly can change the balance of power, save lives and also be effective. President George W. Bush made this mistake with Iraq, when for at least nine months he waited to remove Saddam Hussein and asked for United Nation approval and support, but got none. In the end, his dithering and waiting likely gave Hussein time to hide or destroy his weapons of mass destruction and Bush – to save face when none were then found – sought to disingenuously justify the costly war as an effort to create democracy in this essentially autocratic and factionalized state, run in large part by Muslim terrorist militias in the wake of Saddam's removal. To date, nine years later, there is no real democracy in Iraq; only mostly radical Shiite factions loyal to the mullahs in Iran, not the United States. These factions themselves are on the verge of yet another civil war in the Middle East.
I don't think that most conservative Americans hold the U.N. in high esteem, and they most certainly consider Congressional authorization for military action of far greater importance for a President to seek.
Bush certainly didn't go off half-cocked into Iraq, as is the perception in the liberal psyche. He wasted nine months in attempting to seek U.N. approval. That may have been a huge mistake as the article referenced above indicates. Bush did, however, gain a Congressional Resolution prior to deploying troops: http://en.wikipedia.org/wiki/Iraq_Resolution
And yet liberals perceive Bush as a rabid warmonger.
Obama, on the other hand, didn't even seek Congressional authorization at all, but did rush into military action in Libya at the behest of the U.N. only, in what, less than a matter of weeks? And yet liberals view him as the cool, deliberative, reluctant warrior.