U.S. Navy sailors conduct flight operations aboard the Nimitz-class aircraft carrier USS Carl Vinson in the western Pacific Ocean in this Navy handout photo taken May 2, 2017.

The Navy has three carrier strike groups currently in the Pacific where North Korea's nuclear saber rattling has the U.S. and its Asian allies keeping a close watch on the pariah state.

The last time the Navy operated three carriers together in the Pacific Fleet was back in 2007, and the current show of force comes just before an upcoming state visit to South Korea by President Donald Trump.

"Three carrier groups is certainly a robust force," said Dean Cheng, a defense expert and senior research fellow at the Heritage Foundation, a Washington-based conservative think tank.

Defense experts say the carrier-based aircraft has the ability to perform a preemptive strike against North Korea and fleet escort ships could fire cruise missiles. The North's new air-defense system, though, might be capable of intercepting the military aircraft and missiles.

"This gives us the ability to actually do something as opposed to other kinds of military-symbolic gestures," said Denny Roy, an Asia Pacific security expert and senior fellow at the East-West Center, a think tank in Honolulu. In the past, he said, the U.S. has tended to use symbolic flights of aircraft along the border or sending a single ship near North Korea.

The carrier power in the Pacific comes as the Pentagon's top general — Marine Corps Gen. Joseph Dunford, chairman of the Joint Chiefs of Staff — is in South Korea to meet with leaders of South Korea's military "to examine strategies, plans and means needed to deter any North Korean aggression," according to the Department of Defense.