Re: "The first contact ... could be confirmed over several years"
Even for those of us who are curious about the world, any 'experiment' that will definitely take longer than our lifetime is a lot less interesting to us than something with a more immediate return. Instead of shooting lasers in random directions all over the galaxy, spend that money on a really top notch telescope array sited at multiple points along the Earth's orbit, so you can do parallax at 2AU. We'd be able to SEE if Trappist is inhabited.