I know the US has had treaties thru NATO and SEATO(Southeast Asia Treaty Organization)
I remember things long past. I remember being in indoctrination class aboard
John F Kennedy in April 1972 and the officer in charge (OIC) explaining that there was a treaty with NATO requiring the US to keep two carriers in the MED at all times. This went on for years..into the late 70s or early 80s. Then who knows? Not me. That changed more than likely because of the oil crisis that have risen up from time to time in the last 40 years...and aboard Midway in a similar indoctrination class in August 1973 the OIC stated there was some sort of agreement with SEATO nations that the USN keep one carrier in the western Pacific at all times...There has been a carrier homeported in Yokosuka Japan since October 1973.
Midway, Independence, Kitty Hawk, George Washington & Ronald Reagan.
ATLANTIC OCEAN (March 19, 2020) Lt. Scott "Gameday" Gallagher lands an F/A-18F Super Hornet, attached to "Blue Blasters" of Strike Fighter Squadron (VFA) 34, for the 1,000th trap on USS Gerald R. Ford's (CVN 78) flight deck during flight operations. Ford is currently underway conducting its flight deck and combat air traffic control center certifications. (U.S. Navy photo by Mass Communication Specialist 1st Class Gary Prill)
ATLANTIC OCEAN (March 19, 2020) Sailors assigned to USS Gerald R. Ford's (CVN 78) air department conduct flight operations with an F/A-18E Hornet, attached to "Ragin' Bulls" of Strike Fighter Squadron (VFA) 37, on Ford's flight deck. (U.S. Navy photo by Mass Communication Specialist 3rd Class Zachary Melvin)
ATLANTIC OCEAN (March 17, 2020) Sailors assigned to air departments crash and salvage team stand watch on USS Gerald R. Ford's (CVN 78) flight deck. (U.S. Navy photo by Mass Communication Specialist Seaman Apprentice Riley McDowell)
ATLANTIC OCEAN (March 17, 2020) A Sailor assigned to USS Gerald R. Ford's (CVN 78) crash and salvage team looks on as a MH-60S Sea Hawk helicopter, assigned to the "Tridents" of Helicopter Sea Combat Squadron (HSC) 9 prepares to take off from the ship's flight deck. (U.S. Navy photo by Mass Communication Specialist Seaman Apprentice Riley McDowell)
ATLANTIC OCEAN (March 19, 2020) Sailors assigned to USS Gerald R. Ford's (CVN 78) air department taxi an MH-60S Sea Hawk helicopter, assigned to the "Tridents" of Helicopter Sea Combat Squadron (HSC) 9, on USS Gerald R. Ford's (CVN 78) flight deck during flight operations.(U.S. Navy photo by Mass Communication Specialist 3rd Class Zachary Melvin)