You're forgetting or don't know about WW2.
It was the right wing America First antisemitic fascists that admired Hitler and opposed entering the war. Yes they were called America First. Trump copied them.
Of course progressive FDR knew that the US must be involved.
Not saying FDR was perfect.
Just refuting your point.
It depends on the war.
Of course the Bush invasion of Iraq was a massive mistake.
But getting involved in WW2 was a necessary war as is supporting Ukraine against the genocidal fascist dictator Putin.