Given that President Obama's Libya policy does not seem too popular these days, I want to take a step back from the current situation to consider more generally the perspective presidents have taken since WWII. We can start by asking why presidents thought the WPR was unconstitutional. One standard answer is that the 60 day clock conflicts with the C-in-C power. I think it is more helpful and goes a long way to explaining why presidents have acted as they have if we see what some are calling a "war" in light of the president's power to conduct foreign affairs. Growing up as I did during the days when ideas of the "imperial presidency" held sway, I've had difficulty channeling the presidential perspective I set forth below. But I'm convinced that it lies at the heart of what pro-Congress scholars call the "war powers" debate.
From the president's perspective, the use of military force (and not "war") is one necessary component in the carrying out of the foreign affairs and national security policy of the US. Presidents have had good reason to believe as a matter of history and practice that they are in charge of conducting foreign policy. In addition, there is little doubt that they are held electorally accountable for successes and failures in this area, while Congress is not. And further, there is some text and original intent (which I did not appreciate fully when I began my project) to back up presidential power-claims in this area, quite apart from the C-in-C power. Everyone should check out the important work done by William Casto and Michael Ramsey on the vesting clause in this respect.
You might say that from a presidential perspective, the WPR has to be unconstitutional, regardless of Congress's broad Article I powers. It purports to govern all types of military actions involving "hostilities," requiring withdrawal without mandating a congressional vote. Presidents know full well there are all sorts of ways Congress can avoid voting and taking responsibility. One way is on display right now. Members of Congress say the president hasn't done enough to justify the Libya operation. Friends, this is an old dodge. It was used on Bush I in the run-up to the 1991 Gulf War. It's a way of saying: "I can't really refute your argument and don't want to try to articulate an alternative, but I don't like this." That's not legislative responsibility at its finest. More generally, foreign policy can't be done on a clock. Sixty days gives the president too little time and our enemies too much notice. (Mind you, I think the WPR is constitutional. The postwar responsibilities we have placed on presidents are thus somewhat inconsistent with the original constitutional plan. That's the problem).
Presidents see policy and constitutional issues as tangled together in the area of foreign affairs and war powers. What would justify separating them? Some presidents and their advisers have been willing to concede that congressional approval is constitutionally required for a true war, "total war" as John Yoo puts it. You know, like WWII. This of course is too narrow under any reasonable reading of the "declare war" clause, because it means no president has to get Congress's approval unless another world war breaks out. True, we have had some resolutions lately. But President GHW Bush was going to start a war in the Gulf even if Congress had voted him down. And President GW Bush didn't need to ask because the country had been attacked. The Iraq war resolution was platformed from the 9/11 events. So this doesn't show that recent presidents have conceded resolutions are required for lower-scale military operations.
Along this line, we might ask why Obama isn't getting the benefit of the doubt Reagan received. Reagan launched aggressive military exercises aimed at Libya and a large one-day bombing raid. But Reagan also approved a long-running operation in 1987-88 that reflagged Kuwaiti oil tankers as US ships protected by the Navy. That involved Iran shooting at US crewmen, sailors and multiple strikes in response. The Senate debated the applicability of the WPR, but took no action. This is a clear precedent for the non-applicability of the WPR to the current situation, which has lasted a fraction of the time of the reflagging operation and has not resulted in any US casualties. This of course cuts no ice with Republican House members, but they are likely taking advantage of this opportunity to express their opposition to Obama generally, rather than engaging in any reasoned discourse about our foreign policy. Hence the disconnect between the White House and the House.
As you may be able to tell, I am sympathetic to the idea that Libya does not involve "war," although "hostilities" is a closer question. Calling every military operation since WWII "war" has no prior basis in law, history, precedent or anything else. Former Yale professor (now State Department Legal Adviser) Harold Koh recognized this in his book the National Security Constitution, noting that the WPR did not contemplate today's more limited strike operations. And I wish we could calm down on the subject of war, since so many Americans have died in the real wars we have conducted since WWII -- Korea, Vietnam, the Gulf, Afghanistan, Iraq. I think it trivializes the efforts of those who served in those tremendous, though controversial, wars to call everything "war." Culturally, we know what war is. Real wars are memorialized (or will be) in our sacred spaces, like the Mall. Near the Lincoln Memorial. Those are wars. Libya is not.