Disagree. We never should have gotten involved in that conflict. Once it became clear in 1956 that the result of a nationwide election would be an Ho Chi Minh victory that should have been the handwriting on the wall.
As for draining the Soviets of funds, I am not sure of your source of info on that but the war certainly sucked quite a bit of cash for our treasury. The late 70’s inflation was a consequence of this.
And the rest we say, is history...