Sure, but it doesn't need to happen here. If we get into a WW3 situation, we need to be able to protect our supply lines, and that can happen with friendly countries. We're unlikely to get into a situation where our navy is outmatched, so I don't think it's totally urgent to bring production back here.

That said, we do have a lot of critical manufacturing capacity. Intel has chip fabs, we produce lots of oil, we build cars, etc. We import a lot more than we used to, but we could probably make it through a major war with only domestic production, provided it doesn't drag on too long until we can reestablish supply lines.

I'll only get worried when China catches up in tech. That's certainly happening faster than I'd like, but I don't think China is ready to compete head to head on tech just yet. If they're at parity, that's when we need to worry about domestic production. Ideally we can improve diplomatic ties by then.