The U.S. killed a very bad Iranian. Iran threatened to retaliate.
Draft-age young American men went to the Selective Service web site in droves. So many tried to log on that they caused some glitches.
A note from a veteran...it takes months to train you to be a member of the armed forces. If it goes crazy in the middle east, the soldiers currently under arms will take care of the problem.
Go for a nice drive. Calm down.