President George H.W. Bush gave this speech to the United States when commencing the Gulf War (sorry for the title, but is the shortest clip I could find). In his speech, he notes that there is a broad coalition of support for the war against Iraq. He also laments that force had to be used, after diplomatic options have been exhausted. Personally, and I think many would agree with me, I believe President Bush was spot on. The president and/or those advising him understood the international order and the necessities of multilateral diplomacy to achieve desired results.
In Fareed Zakaria's The Post American World, he makes note that America has to procure a "cadre" of international support in the modern era (not that 1991 wasn't modern, but things have changed). I completely agree with this. The support of this concept may reflect the neo-liberal part of me, but if the past decade has been any indication, it is that Zakaria is right. Yes, we did have allies go into Iraq with us in 2003, but it lacked the international legitimacy that we had in 1991. In 1991, we had a UN resolution behind us, and the fact that we tried extensive state diplomacy and public diplomacy. William Rugh's American Encounters with Arabs gives a detailed account into the diplomatic actions President Bush took before resorting to force.
In the modern international order, the U.S. cannot afford to act unilaterally anymore. As shown by the Gulf War example, the U.S. showed leadership without unilateral action. This concept is indeed possible. Now, I am not saying that we always need that broad of a coalition, but the U.S. should pursue policy similar of gaining international consensus, especially for actions in the Middle East. The situation in Iraq was efficiently diffused through smart diplomacy. By exhausting diplomatic options, it sent a clear signal that the U.S. tried a multitude of different options before calling for force. This increased the view of the U.S. among many in the world not as a benevolent hegemon, but as a responsible leader. In what looks like a decreasing sense of U.S. hegemony, I think it would be smart to heed Zakaria's points. A more multilateral foreign policy should be good for U.S. policies in containing Chinese influence and for our Middle Eastern relations. American Exceptionalism (which often translates into unilateralism) is not a bad idea, but it lacks proper place in the current world system.
Whether some want to believe or not, the world is much more interconnected than ever before. In a world entangled in the web of technology (no pun intended), it is imperative the U.S. adapt and pursue policies similar to the way George H.W. Bush handled the the pre-action and Gulf War. He did it right. The age of unilateralism for large operations is over...for now.