Stocks fall as Boehner announces support of Obama on Syria

The Dow Jones Industrial Average started the morning strong, rising nearly 132 points to 14933.35 before Obama met with congressional leaders on his call to punish Syria for allegedly using chemical weapons on Syrian civilians. 

Stocks had responded in part to robust manufacturing data. The sector expanded last month to 55.7, up from 55.4 in July, the strongest period all year and the best showing since June, 2011, suggesting that activity may be gearing up again, the Institute for Supply Management reported on Tuesday.

After the meeting, BoehnerJohn Andrew BoehnerA warning to Ryan’s successor: The Speakership is no cakewalk With Ryan out, let’s blow up the process for selecting the next Speaker Race for Republican Speaker rare chance to unify party for election MORE said, "I'm going to support the president's call for action, and I believe my colleagues should support the president's call for action." House Majority Leader Eric CantorEric Ivan CantorRace for Republican Speaker rare chance to unify party for election Scalise allies upset over Ryan blindside on McCarthy endorsement 2018 will test the power of political nobodies MORE (R-Va.) also issued a statement of support. The two statements make an attack on Syria more likely. 

Once the Boehner publicly said he would support the president, the Dow quickly fell more than 100 points.

At midday, the Dow was in negative territory at 14798.03. 

The S&P 500 had risen 16 points to 1651.35 before the congressional meeting with Obama ended but had lost most of those gains in the aftermath. 

An attack on Syria has the potential to increase turmoil in the Middle East, source of much of the world's energy supply.