As reported in the media, the United States is planning a cruise missile attack against the Syrian government. This attack would be an act of war against a government that has not attacked or declared war against the United States. As required by the Constitution, the President must seek authorization from Congress to initiate war.
In addition to the legality of any military strike in the absence of such authorization, drawing the United States into a civil war in a foreign country is a act of dubious merit.
Given that the Syrian civil war has been ongoing for an extended period, and that it is likely to continue, there is ample time for Congress to deliberate and hear from the people on this issue before hastily committing American blood and treasure.