Last week the US and South Korean Army and Air Forces participated in a massive live-fire exercise in Pocheon, an area about 50 miles north of the South Korean capital of Seoul and about the same distance from the North Korean border.
The following video shows some of the forces involved in the exercise, and the amount of firepower on tap with these combined forces is both intense and impressive:
The opening four minutes of the video shows an assortment of artillery and air strikes that would be undertaken to soften-up a target in prior to ground forces moving in. A number of Korean and US aircraft are shown on bomb and gun runs, including the A-10, F-16, F-15, AH-64 as well as Multiple Launch Rocket System (MLRS) and artillery strikes.
Next, almost exactly at the 4 minute mark, come the ground forces. Large numbers of Abrams tanks, still supported by close air support, roll into the area to take out the "enemy tanks" (painted tarps) with impressive accuracy. At 6:30 in the video a couple of tanks release a smoke screen which allows additional forces to move up and leapfrog the initial line of tanks.
At 7:15 a transport helicopter delivers some special forces via fastrope, with additional helicopters bringing in their heavy equipment - jeeps, towed artillery, etc. At 8:45 the mechanized infantry shows up in a long formation of APCs. From here until the end of the video we see a large show-of-force with paratroopers and large formations of both fixed- and rotary-wing aircraft.
This military exercise came during a period of great tension between both North and South Korea, however negotiations between the two countries have recently been able to deescalate the situation before any large-scale conflict began. It's difficult to say if these exercises helped or hindered the discussion between these two constantly-feuding neighbors, but at the very least they likely gave a little pause to the North Korean leadership.