I have no idea what policy in Syria would be effective in protecting that country's people from their murderous government, ending the country's murderous civil war, blocking increased influence by Iran and Russia in the Middle East, and stemming the rise of the Islamic State. I do not know which of the armed groups fighting against the government of Bashar al-Assad are fighting for something like democracy and which are seeking religious or ethnic dictatorships. I can't tell you how a global superpower can affect the political and military outcome of a multi-sided civil war without itself becoming involved in ground operations and even occupation—and dangerous conflict with other major powers.
Wise heads in the Pentagon and the National Security Council may actually have a plan; they may know friend from foe; they may have imagined the next step, and the next, wargaming intelligent American responses in the likely event that things in Syria do not immediately fall into place.
But I don't know. No one outside the small world of national security knows. The president has not even pretended to tell us whether he has any plan at all, and if so, what it is.
Indeed, from his statements on Thursday, it seems at least possible that, moved by the horrific video images of Syrian children suffocated by a gas attack, Trump simply decided to "do something" because, as he said in his statement, "No child of god should ever suffer such horror."
The impulse to act without thinking would be understandable. Careful planning and clarity of purpose aren't easy in a fast-moving international situation. But the framers of the Constitution constructed a mechanism to reduce or eliminate the danger that a president would take the nation to war on a fleeting impulse.
They gave the power to initiate war not to the president but to Congress.
Article I § 8 cl. 11 gives Congress the prerogative to "declare war." The powers surrounding that grant suggest that everything about the choice of war is a congressional power. Article II § 2 cl. 1 makes the president "commander in chief of the Army and Navy ... and of the militia”—but the context doesn't suggest that is the power to "command" the entire nation into war. In fact, the original wording of Article I gave Congress the entire power to "make war," with nothing given to the president. The Convention amended the words to "declare war," in order to give the president the narrow power to, in the words of Madison's Notes, "repel sudden attacks."
Roger Sherman of Connecticut objected that the wording gave the president too little power. He was rebuked by Eldridge Gerry of Massachusetts, Oliver Ellsworth of Massachusetts, and George Mason of Virginia, who all agreed that reposing the war choice in the executive would be dangerous.
"Mr. GERRY," the Notes record, "never expected to hear, in a republic, a motion to empower the Executive alone to declare war." Though often flouted by overreaching presidents and craven Congresses, that division of power remains the law of the land.