“For seven days, we conducted real-world, constructive operations inside the First Island Chain,” Col. Jeremy Winters, who commands MACG-38, 3rd Marine Aircraft Wing, based at Miramar Marine Corps Air Station in San Diego, told an audience at a panel discussion on multi-domain operations and expeditionary kill webs. – USNI News
That is a very interesting paragraph. The First Island Chain is this:
“The first island chain refers to the first chain of major Pacific archipelagos out from the East Asian continental mainland coast. It is principally composed of the Kuril Islands, the Japanese archipelago, the Ryukyu Islands, Taiwan (Formosa), the northern Philippines, and Borneo, hence extending all the way from the Kamchatka Peninsula in the northeast to the Malay Peninsula in the southwest. Some definitions of the first island chain anchor the northern end on the Russian Far East coast north of Sakhalin Island, with Sakhalin Island being the first link in the chain. However, others consider the Aleutian Islands as the farthest north-eastern first link in the chain.[citation needed] The first island chain forms one of three island chain doctrines within the island chain strategy in US foreign policy.[1]
Much of the first island chain is roughly situated in waters claimed by China.[2] These include the South China Sea, within the nine-dash line, as well as the East China Sea west of the Okinawa Trough.”
So basically right in front of China.
Marines Testing Battlefield Networks for Future Conflicts