U.S. Marines with 2nd Battalion, 23rd Marines, forward deployed with 4th Marine Regiment, 3d Marine Division as part of the Unit Deployment Program, form a stack as they prepare to enter a building as a part of military operations in urban terrain training during Korea Viper 25.4 at Pohang, South Korea, May 3, 2025. Korea Viper is a recurring exercise series that demonstrates the Republic of Korea and U.S. Marine Corps' ability to respond decisively in the region as a singular, unified force while strengthening relationships and trust between the two allies. (U.S. Marine Corps photo by Lance Cpl. Tucker Mocan)