Yes and no. The Iran war is deeply unpopular and won’t even pass congressional approval for money. It’s being fought from pocket change budgets because they know they can’t pass a funding bill for it. Also not the same kind of war.

Any period time? US waged war for 20+ years in Afghanistan. Pretty effectively! To what end? Not an end an army can really achieve so… there you are.

But a war that might actually be popular? To save the world from communist dictators and make sure we have chips for our precious devices? I wouldn’t count out the United States. Or nuclear weapons, which still exist and are a thing.

And it'd be the kind of war the US is best at. Boots on the ground, against conventional military, with a civilian population that is on the side of the US forces

No guerilla warfare, no insurgents, no need for extended beyond-visual-range warfare that depletes missile stockpiles