That’s even more ridiculous.
Imagine what a cowardly weak signal that would send to future allies.
Future allies? What is an ally exactly? If the states were fighting against Mexico which one of our “Allies” would join in? Allies are there when it serves their needs. The Kurds are allies only in that the U.S was their best option. Look, now they are allies with Russia and Assad again...why? That’s their best option. There will always be allies because there will always be people who approve and whose needs meet yours. With the possible exception of Britain I don’t think their is a country who will ALWAYS be allies in all situations. See Iraq war