By any rational reckoning, firing missiles into a country is waging war on it. Congress has the sole authority under the Constitution to declare war.
In some circumstances, such as when an immediate threat to Americans or U.S. interests exists, presidents are right to take military action.
There is no such threat in Syria - but President Barack Obama is considering an order to launch a missile attack on that country because of a report it used chemical weapons against foes in its civil war.
Many members of Congress, of both political parties, do not agree with the president. Neither do many other Americans.
Clearly, this is a situation in which Congress - by an emergency session, if need be - needs to intervene.