Exactly: in political rhetoric, the Laffer Curve is 5% an honest examination of tax tradeoffs and 95% a trojan horse designed to smuggle into the conversation the assumption that we are on the "drowning in taxes" side of the Laffer Curve.

I think there's also the consideration that the Laffer curve is very Ceteris Paribus.

In reality higher taxes implies higher spending, and different countries spend differently. It's entirely possible that the peak of the curve moves based on where you plan to spend the money. If you proposed a 5% tax increase to build the supports to take on Taiwan in semi, then you probably have a curve that looks different than a 5% tax increase to start a war.