In the early stretches of the seven-year Syrian civil war, President Barack Obama proclaimed a clear mission: Syrian President Bashar Assad had to go. Assad didn’t.

Then Obama dared Assad to cross a U.S. red line on the use of chemical weapons in the war. Assad did.

Assad suffered no serious consequences. Obama eventually allowed limited U.S. military involvement and put faith in a brokered arrangement by which Syria supposedly would relinquish its chemical weapons. Congress never has had any stomach for declaring what this nation’s role in Syria’s civil war should be. As years dragged on, the war has claimed some 400,000 or more lives. Why the U.S. indecision?

Obama was fearful of drawing the U.S. deeper into the civil war. President Donald Trump shares that fear. He has focused on defeating Islamic State — a formidable task largely achieved. He is eager to pull the last 2,000 U.S. troops out of Syria.

This meandering maybe-we-will-maybe-we-won’t path led to Friday night’s missile strikes against three Syrian chemical weapons facilities. “Mission accomplished!” Trump tweeted after America’s military unleashed more than 100 missiles.

Yes, this attack should help hobble Assad’s ability to drop those horrific weapons on his own citizens. But this episode doesn’t answer the overarching question: What is the U.S. mission in Syria now — if any? We think Americans largely agree on two agendas — both important, one broad, the other narrow:

The broader agenda is that Islamic State still poses some level of physical and inspirational menace to the world. This group must be eradicated. On the ground, that goal is nearly accomplished, but will require U.S. vigilance over the next years to ensure the group does not reconstitute itself.

The narrower agenda is that the U.S. and its allies will defend international laws against chemical weapons and retaliate against countries that use them. That’s a critical message to send, again and again if need be. No regime should feel it can gas its citizens without severe consequences.

Beyond those two points, American leaders and citizens have no consensus. Some want an isolationist approach in which Washington does next to nothing. Others want a more muscular approach, to topple Assad and to keep Russia and Iran from cementing Syria into their Mideast spheres of influence.

We’ve backed the effort to crush Islamic State. And we support Trump’s Tomahawks against chemical weapons plants that should have been shut long ago.

But face facts: Russia, Iran and Turkey still largely determine the future of Syria. Barring military and other pressures that a majority of Americans likely wouldn’t endorse, the U.S. will be a marginal player.

Assad and his handlers knew before using poisonous weapons that Trump would answer with the sort of retaliation he ordered used Friday. The Syrians want U.S. troops out of Syria; they could have waited Trump out, let him withdraw the troops and then attacked Syrian civilians. Instead, Assad chose to press his overwhelming advantage. A few missiles, that he can tolerate. He knows he won’t incur an outsize U.S. reaction.

In sum, this strike by Western militaries didn’t change the dynamics of the civil war that is largely over. Yes, Friday’s attack did underscore a comparable assault on Syrian facilities last April: Assad invites increasingly fierce retaliation if, in his zeal to crush the militants trying to depose him, he uses chemical weapons. But that 2017 assault didn’t intimidate Assad. We’ll see whether the results in 2018 are any different.

Friday’s strikes won’t satisfy the American isolationists who think the U.S. has no interests at stake in Syria, or the more bellicose Americans who hoped for heavier strikes to debilitate Assad’s military.

But after seven years — first with a timid U.S. president and now with a conflicted U.S. president — there’s no American agreement on what this nation should do. Absent a more ambitious and effective Syria policy, occasionally curbing Assad’s most brutal tendencies will have to do.