How would you react if our world became under attack from intelligent beings not of this Earth?

my first move would be laugh so hard at all the idiots who would believe such ruse created by the government, another boogieman as one could say! i t would not surprise me if the government did that, a few month ago they claimed aliens invading there missile bases, they are sending satelites with missiles that can reach anywhere on earth within seconds! so if they did that i would just laugh! remember they can do whatever they like nowadays!