Vice President Mike Pence with US service members in Tokyo on April 19. AP Photo/Eugene Hoshiko Vice President Mike Pence stood on the deck of the USS Ronald Reagan in Yokosuka, Japan, on Wednesday and reassured thousands of US Navy sailors and regional allies that "the sword stands ready" to strike at North Korea's Kim regime.

But President Donald Trump's administration has said this time and time again.

The four most important words Pence has said on his Asia trip so far were in response to a key question: Will the US talk to North Korea?

"Not at this time."

Pence has repeated nearly verbatim statements from Secretary of State Rex Tillerson on the US's strategic patience ending with North Korea, and other military threats by other administration officials.

But his words aboard the Reagan about an "overwhelming and effective" response to any use of conventional or nuclear weapons by North Korea rang hollow.

The US Navy has told Business Insider that the forward-based Reagan will be tied up for months with refittings and training exercises. In a perplexing mix-up, the USS Carl Vinson, which the US Navy said on April 8 would head to North Korea, was photographed 3,500 miles away in Indonesia on April 15.

South Korea's conservative candidate for its May presidential election, Hong Joon-pyo, told The Wall Street Journal of the carrier mix-up: "What Mr. Trump said was very important for the national security of South Korea. If that was a lie, then during Trump's term, South Korea will not trust whatever Trump says."

The aircraft carrier USS Carl Vinson. US Navy photo by Mass Communication Specialist 2nd Class Sean M. Castellano

On both the North Korean and US sides of the conflict, all talk of military action can likely be dismissed as bluster.

North Korea has promised "nuclear thunderbolts" and "all-out war," but any conflict between the US and Kim Jong Un's regime would likely be bloody and result in the near destruction of North Korea, unacceptable civilian losses in South Korea and possibly Japan, and the devastation of US military bases in the region by missile and artillery fire.

None of the dozen or so North Korea experts contacted by Business Insider said large-scale military action against the regime was credible. China must know this. North Korea, on some level, must know this.

North Korea has repeatedly offered to scale back its nuclear program if the US stops its annual military drills with South Korea. The US has dismissed this, saying that planned, regularly occurring military exercises that have gone on for 40 years without leading to war can't be equated to a state that often threatens to nuke its neighbors.

North Korean soldiers at a military training in March 2013. Reuters/KCNA

Trump has brought two ideas to the North Korean stalemate: threaten military force, and leverage the US's trade relationship with China to force its hand against the Kim regime.

But military force wouldn't work, and there's not much China can do.

In light of the failure of military and economic measures, diplomatic engagement looks like the only option left, but Pence has made the US's stance on this clear: "Not at this time."