Finally, the White House has a poll showing at least a roughly even split on taking action against Syrian dictator Bashar al-Assad for using chemical weapons. According to a new NBC/Wall Street Journal poll, 50% oppose military action, but that changes to 50% approval if only long-range missiles are used rather than sorties using pilots. However, almost eight in ten believe that Barack Obama has to get authorization from Congress before ordering any kind of military action at all:

In this new NBC poll, 50 percent of respondents oppose the United States taking military action in response to Syria’s use of chemical weapons, compared with 42 percent who support it. However, those numbers flip when the military action is defined to mean launching cruise missiles from naval warships – 50 percent favor it, while 44 percent oppose it. And 58 percent agree with the statement that the use of chemical weapons by any country violates a “red line” that requires a significant U.S. response, including the possibility of U.S. action. Still, a whopping 79 percent of respondents – including nearly seven-in-10 Democrats and 90 percent of Republicans – say the president should be required to receive congressional approval before taking any action.

On top of that, only 21% are buying Obama’s argument that an attack on Assad is in the US’ national interest, and more people say it will make the situation worse for Syrian civilians (41%) than improve their lot (27%). Both of these measures have a large group of respondents unsure of their position (45% on American interests, for instance), so Obama has some room to improve his standing. Since Obama has decided — at least so far — not to address the American people on launching a war, though, the opportunities to make converts out of the unsure will be few, let alone the opposed.

Furthermore, even this level of enthusiasm may be an outlier. A Huffington Post/YouGov poll earlier this week put support for air strikes at 25%, with 41% opposed. The Christian Science Monitor/TIPP poll this week put opposition in the majority, 52% to 39% supporting air strikes. The Monitor and Newsmax also reference an earlier Reuters/Ipsos poll putting opposition at 60%. Pushing forward on a military action this unpopular without seeking Congressional approval would be a political disaster for Obama, even if it turns out not to be an strategic disaster, a la Libya.

Speaking of disasters, the rest of the NBC/WSJ poll is bad news for the White House, too. As Obama prepares to take the nation to war, he’s hit his lowest approval rating in this series since November 2011 at 44%. Obama also hit his lowest approval rating in foreign policy ever at 41/49. Specifically on Syria, he has an approval/disapproval rating of just 35/44. This is not a President with a mandate to act unilaterally on foreign policy, let alone taking the nation to war.