Pushing Russia, China, Iran, and North Korea into a de facto alliance

That is exactly what U S. foreign policy has done.

Perhaps the most determinative thing is U.S. support for Ukraine.

That clearly pushes Russia away from the U.S., into an alliance with those other countries.

This clearly, IMO, a terrible policy.

There is such a thing as having too many enemies.

Making Russia an enemy was, and is, clearly a big mistake.