If we want to be the world’s main superpower, then we will always have enemies.
Do you think the Russians would be better? The Chinese? Either there will be a dominant power or their will not.
A world without a dominant power is unstable, as we learned from WWI and WWII. The British had been dominant. Then they succumbed to the siren call of disarmament.
The U.S. grew and succeeded under the wings of British enforcement of freedom of the seas, and a world order of sorts.
Just as South Korea, Europe, and China have flourished under a pax Americana.
Granting everything you say, the statement is still true.
As to whether the country should commit the blood and treasure to be the dominant superpower is a decision we the people make by choosing our leaders. It is an interesting speculation as to how the Founding Fathers would have viewed things if why knew that eventually our power would be nearly enough to defeat the rest of the world put together.
In a way, that’s what lead to the fall of the Roman Republic; not so much the decadence (or otherworldliness) of the people but the fact that a form of government well suited to a vigorous and expanding republic did not work for running a world empire.
Can there be an empire that does not sow the seeds of it’s own destruction by the eventual decline into hubris on one hand or complete impotence on the other?
I have no answers, only the opinion that *if* we want to be #1, then yes, we will always have enemies.