Sorry, it's late and I didn't read all the posts.
There is a law against what the US citizens did at the conference. If the individuals signed that resolution, they should be held legally accountable.
Treason and/or sedition, giving aid to the enemy, whatever.
I think they may have gone a little too far this time.
They did not violate "law" they violated the Constitution.
The only way to make what they did okay is to amend the Constitution.
The question remains, will Congress take up their Constitutional duty and convict these traitors and sever their support in America?
It is listed in the Constitution near impeachment.