That's how the game is played.Often when some group of people want something from the government (ie change laws to suit them, monetary benefits, business deals with government etc), they get a powerful lobby group to lobby for their cause.
Scientists do it it. Scientists are an extremely powerful lobby, because if you can get a group of physicists to say "look if you do X, I can't guarantee that the US will still be able to make nuclear bombs that work", then people will listen to you.Big business do it, maybe the scientists could do it to.
Scientists also have very powerful allies among big business and the military. If you get a dozen physicists to say "this is just going to kill your profits" then CEO's start to listen.
The only problem here is crying wolf, but the wolf is coming this time.
You don't need a huge amount of money to play politics, and as far as connections, physicists have them.Only shortcoming I see (and it is a big one), is that you need money (money talks) and maybe connections to do it.
Also if you are interested then do what the letter says.