Two B-2 Spirit stealth bombers and two B-52 Stratofortresses flew nearly 8,000 miles nonstop over more than 20 hours from the mainland to Hawaii and back Wednesday to conduct long-range strike training at Pohakuloa Training Area on Hawaii island.

And to impress defense ministers meeting in Honolulu from the 10-country Association of Southeast Asian Nations, or ASEAN.

The four bombers conducted "low-approach training" at Joint Base Pearl Harbor-Hickam about 3:30 p.m. while the defense ministers toured the base and saw static aircraft, officials said.

The B-52s were flown from Barksdale Air Force Base, La., and the B-2s from Whiteman Air Force Base, Mo.

The delegation had just come from a visit to the state-of-the-art $1.3 billion amphibious ship USS Anchorage, which sailed from San Diego to Hawaii for the first-ever U.S.-hosted ASEAN defense forum.

Much of the high-tech firepower was framed for its dual-use capabilities in humanitarian assistance and disaster relief situations — common ground for the United States and ASEAN nations in the disaster-prone Pacific.

But Ralph Cossa, president of the Pacific Forum Center for Strategic and International Studies in Honolulu, noted before the conference that the technology also demonstrated "that we’re still the most powerful military in the world."

The United States wants to reassure Asian allies and friends who are worried about China’s increasing challenges to the Pacific status quo that its rebalance of forces to the region is real and that it is committed to regional security.

U.S. Strategic Command, headquartered at Offutt Air Force Base in Nebraska, said B-2 and B-52 aircrews regularly participate in nonstop round-trip training missions from home stations.

"As such, approximately one to two nonstop long-range strike training missions from the continental United States to training ranges within the vicinity of Hawaii are scheduled annually," the command said in an email.

The command did not specify which training ranges.

Strategic Command said the long-range training flights help ensure that bomber crews stay proficient in combat capabilities, command and coordination and familiarity with the area of operations.

The Hawaii bomber training mission was scheduled several months before the announcement of the ASEAN conference in Hawaii, it said.

"Because Joint Base Pearl Harbor-Hickam is a primary location for our pilots to conduct contingency/emergency operations," Strategic Command said, "it was determined that we would conduct the airfield familiarization portion of the training at the same time the ASEAN delegation was at Joint Base Pearl Harbor-Hickam to not only train our pilots, but also showcase our aircraft capabilities which reinforce commitment to our allies and partners."

Since 2004, B-1, B-2 and B-52 bombers have deployed on rotational deployments to Guam, and the Air Force sent B-2s and B-52s on nonstop "Koa Lightning" exercises from Guam to Hawaii to drop dummy ordnance at Pohakuloa.

In November, the United States defied China by flying two B-52s from Guam into airspace over the East China Sea where China declared it was establishing an "air defense identification zone."

In March 2013, meanwhile, Strategic Command sent two of its B-2 "batwing" nuclear-capable stealth bombers on a round-trip mission from Missouri to South Korea for exercises after weeks of North Korean provocation.

The Kansas City Star estimated the cost of the mission at $10,000 per flight hour.

Each of the four aircraft sent to Hawaii Wednesday conducted two midair refuelings.

A total of 14 inert practice bombs were dropped at Pohakuloa — eight 500-pound BDU-50s by the B-52 aircrews and six 2,000-pound BDU-56s by the B-2 crews, Strategic Command said.