Poll: 4 Out of 5 Americans Say Obama Needs Congressional Greenlight for Syria Strike

Half of all Americans want President Obama to launch a missile strike on Syria, but nearly 80 percent want him to get congressional approval first, according to an NBC News poll.

The poll, conducted Wednesday and Thursday, reveals a nuanced, or perhaps contradictory, attitude about the use of force. Only 42 percent of poll respondents said they supported "military action" against Syria, while 50 percent were opposed. But support for action jumped to 50 percent—and opposition dropped to 44—when respondents were asked specifically about "military action … limited to air strikes using cruise missiles launched from U.S. naval ships."

Finally, 58 percent of respondents agreed that the use of chemical weapons by any country is a "red line" that requires "a significant U.S. response, including the possibility of military action," while only 35 percent disagreed.

Respondents were much more unified when asked about whether Obama should require congressional approval before getting the military involved in Syria, with 79 percent agreeing and only 16 percent opposed.

The poll's authors put its margin of error at 3.7 percentage points.

Scholars support a broad range of positions on how much authority the president has to attack another country without legislative approval. But regardless of the legal text, the on-the-ground reality is that Congress has been largely unsuccessful in stopping presidents from launching strikes without approval, said James Lindsey, director of studies at the Council on Foreign Relations.

Obama did not secure congressional approval for the country's most recent military intervention in the Arab world, a series of strikes in Libya aimed at toppling the regime of Muammar el-Qaddafi.