Most Americans say they support U.S. participation in a no-fly zone over Libya as a way to neutralize Libyan leader Moammar Gaddafi’s air force, according to a new Washington Post-ABC News poll.

But support slips under 50 percent when it comes to more unilateral U.S. action, as Democrats and independents peel away. And under either scenario, about a quarter of all no-fly advocates turn into opponents when the specifics of the military action are detailed [bold mine-DL]. ~The Washington Post

Put another way, a slim majority favors a no-fly zone in which the U.S. is just one participant when the respondents don’t have to think very much about what is involved. Once the respondents hear about what is involved, support plummets. The Post/ABC poll‘s question to respondents that support a no-fly zone seems reasonably accurate:

Creating a no-fly zone first requires bombing attacks on anti-aircraft positions, and then requires continuous air patrols. Given those requirements, would you support or oppose using U.S. military aircraft to create a no-fly zone in Libya?

72% of would-be supporters actually support a no-fly zone when confronted with what it would require. That means that just 40% of respondents favor a no-fly zone when the U.S. is one of many participants in enforcing it, and support for a primarily U.S. effort would be lower still.

In light of this, I found Sen. Lugar’s call for a full Congressional debate and a declaration of war before any U.S. military action against Libya to be very encouraging. Considering his exalted view of executive power, I doubt that Obama is unwilling to order military action without a declaration of war, but it’s a very healthy sign that the ranking Republican on the Foreign Relations Committee is insisting that Congress have a major role in making this decision. As the vast majority of the public is against a Libyan war even in the form of a no-fly zone, it is hardly certain that Congress would authorize military action, much less take what is by now a very unusual step of formally declaring war. This is as it should be. War powers were reserved to Congress to prevent the executive from launching wars arbitrarily, and the failure of Congress to rein in presidential abuses in this area and the failure to insist on declarations of war before going to war have been at the heart of many of the most serious foreign policy blunders since WWII. A full debate in Congress might create one more obstacle to the folly of going to war against Libya.