> There is no easy way to stop the Bitcoin network so if they really wanted to kill Bitcoin

I think you underestimate how much pressure the US government can put and how centralized the web is.

If:

No legitimate business will accept Bitcoin.

Twitter, Facebook, Reddit ban all mentions or advocacy of Bitcoin

All public Bitcoin exchanges are shut down.

This would severely curtail Bitcoin and likely actually cause a drop in value.

Yes it is probably impossible to ever get rid of something, but for the government, reducing something to a fringe can be beneficial and is definitely something they can do.