The United States and South Korea combined their naval forces together in a military exercise off Sea of Japan as a show of force against North Korea.

This was a direct response to the testing of nuclear warheads and ballistic missiles by the North Korean military.

In a report by CNN, the drills by both countries show the U.S. guided missile destroyer USS Spruance amalgamated with other warships, submarines and planes armed with long-range, precision, land attack cruise missiles from the South Korean navy.

This is the first time that vessels from both nations performed drill in such a close proximity to the east coast of North Korea that it send alarm bells ringing in Pyongyang. It seems like an act of provocation was what both the U.S. and South Korea were intending to do.

The display of naval power from both countries was a follow up to the flight of United States Air Force B-1 bombers over the Demilitarized Zone. It was the closes to the borders of the Democratic People's Republic of Korea that the powerful and heavy bombers have ever flown. This flight too, was a response following the announcement of what North Korea claimed to be a successful test of rocket engine.

During the first week of September, approximately four days after North Korea's fifth and possibly most powerful nuclear weapons test, the bombers flew to the south of the South Korean capital of Seoul, over Osan Air Base.

Following the successful joint exercises on Monday, Rear Adm. Brad Cooper, commander of U.S. Naval Forces Korea and Task Force 78, said: "We work side-by-side with our ROK partners every day; we are by their side today at sea, and we will remain by their side to defend against North Korea's unprovoked acts of aggression."