I think the whole point of setting up a VPN is to AVOID port forwarding. It’s safer to have no ports forwarded.
Yes, but if the only thing you're forwarding is the VPN, it's fine. There isn't really any big issue with forwarding anyway, the issue is with exposing potentially vulnerable services. And if you take down a service but forget to disable port forwarding, and something you don't want public ends up being accessible from the Internet.
If we're talking actual air raids as in bombing runs, then yeah, it's still useful for illuminating your target. Less so for rocket and artillery attacks.
The feds don't enforce state law.