You should know our mania for building is stronger than ever. It is a diabolical thing. It consumes money and the more you build, the more you want to build. It's a sickness like being addicted to alcohol.
If an alien lands on your front lawn and extends an appendage as a gesture of greeting, before you get friendly, toss it an eightball. If the appendage explodes, then the alien was probably made of antimatter. If not, then you can proceed to take it to your leader.