Washington (CNN) -- It's mid-June, a perfect time to visit the beach to watch porpoises play in the surf or seagulls strut the sand -- or you could watch a formation of Marine Corps warplanes darting over the shore at hundreds of miles per hour. But don't worry -- the United States hasn't declared war on your family's beach house. It's just part of a major Marine Corps exercise called Exercise Mailed Fist (translation: armored fist).