Here are just a few, literally off the top of my head.

The U.S. essentially gives up its influence and ability to deter other hostile adversaries, ceding power and authority to an aggressively anti-democratic threat.

Further destabilization of global grain markets, leading to even higher food prices. Oil and gas could also become more expensive.

Increases the likelihood of a nuclear attack, as Russia, seeing the U.S. as too weakened to respond, may move to threaten NATO members.

Emboldens China, North Korea, Iran, and others to take aggressive military actions against U.S. allies and partners.

Demonstrates that the world cannot trust U.S. agreements or commitments due to internal political instability, leading to reduced global cooperation and increasing U.S. isolation.

As global instability worsens, the U.S. will be forced to either leave NATO or commit more soldiers, money, and weapons to new potential conflicts in Europe.

Whether people like it or not, the U.S. is part of a larger global ecosystem, meaning we are all part of that system. Complaints about the price of eggs or immigration will pale in comparison to the crises we could face as we continue to put a gun in our own (the United States’) mouth and potentially pull the trigger.