North Korea put its army on alert on August 15 but said it would hold off firing any missiles at U.S. territory after the U.S. Pentagon chief warned that such a move could "very quickly" escalate into a war.
In a statement carried by Pyongyang's official news agency, North Korean leader Kim Jong Un ordered his army to always be prepared to launch a missile strike but said he will watch what the United States does for a while longer before making any decision to launch them.
"The United States, which was the first to bring numerous strategic nuclear equipment near us, should first make the right decision and show through actions if they wish to ease tensions on the Korean Peninsula and prevent a dangerous military clash," Kim was cited as saying by his KCNA news agency.
Kim's latest rhetorical volley at the United States came shortly after U.S. Defense Secretary Jim Mattis told reporters in Washington on August 14 that the United States is prepared to "take out" any missile fired at its territory in what he views as an act of war.
"If they fire at the United States, it could escalate into war very quickly," he said. "Yes, that's called war, if they shoot at us."
Mattis said U.S. missile detection and tracking systems can determine quickly whether a missile launched from North Korea is headed for U.S. soil. North Korea said last week it is considering launching four missiles to land just short of the U.S. Pacific island territory of Guam.
If a missile is judged to be headed for Guam, Mattis said: "We'll take it out."
If the Pentagon determines the missile would fall into the sea short of Guam, he said "it becomes an issue we take up however the president chooses."
Mattis stressed that he doesn't want to escalate the war of words with Pyongyang and believes the two nations should settle their dispute over North Korea's development of ballistic missiles and nuclear weapons peacefully.
Mattis noted that he joined U.S. Secretary of State Rex Tillerson in authoring an opinion piece in The Wall Street Journal on August 13 that repeated Tillerson's previous assurances to Kim that America has "no interest" in regime change in Pyongyang or an accelerated reunification of the two Koreas.
The two officials said in the article that "while diplomacy is our preferred means of changing North Korea’s course of action, it is backed by military options."
"We were thinking it would be wise to put out something that shows how the State Department and the Defense Department work together. It's not one or the other; it's the two working together," Mattis said.
The exchange between Mattis and Kim came after the chairman of the U.S. Joint Chiefs of Staff told South Korea's president in a visit to Seoul on August 14 that the United States is prepared to use all the military capabilities it possesses to defend against North Korea, according to a spokesman.
General Joseph Dunford told South Korean President Moon Jae-in that "North Korea's ballistic-missile and nuclear weapons programs threaten the entire global community," U.S. military spokesman Captain Darryn James said.
He said that Dunford "conveyed America's readiness to use the full range of military capabilities to defend our allies and the U.S. homeland."
Meanwhile, a spokesman for Moon told reporters that Dunford said the U.S. military options being prepared against North Korea would be for when diplomatic and economic sanctions failed.
Dunford is also to visit China and Japan this week, amid tension over an exchange of fiery warnings between North Korea and the United States.
He told reporters on August 13 that during his Asia trip he would discuss military options in the event that the "diplomatic and economic pressurization campaign" fails.
"We're all looking to get out of this situation without a war," Dunford said.
Moon called on August 14 for calm in the standoff with the North, saying there should never be another war on the peninsula.
"We cannot have a war on the Korean Peninsula ever again," Moon said. The 1950-53 conflict cost more than 1 million lives and perpetuated the division of the peninsula.
Tensions have increased since U.S. President Donald Trump, responding to the North's latest missile tests, warned that the United States would respond to further threats with "fire and fury like the world has never seen."
The North, in turn, threatened to fire missiles toward Guam, and Trump subsequently said that a U.S. military response was "locked and loaded" -- meaning ready to be put in place at any time.
The war of words has sparked global alarm, with world leaders including Chinese President Xi Jinping urging calm on both sides. China is the North's most important ally and trade partner.
However, Beijing is increasingly frustrated with Pyongyang and joined in approving UN Security Council sanctions on August 5 over the North's nuclear program.
In line with the new sanctions, China on August 14 announced it will stop importing North Korean iron ore, coal, fish, and other goods in three weeks.
With tension high, two leading U.S. national security officials suggested on August 13 that a military confrontation with North Korea is not imminent but that the possibility of war still looms.
"We're not closer to war than a week ago, but we are closer to war than we were a decade ago," H.R. McMaster, Trump's national security adviser, told ABC television’s This Week program.
McMaster said the United States continues to pursue "a very determined diplomatic effort," led by Tillerson, along with new financial sanctions, to discourage North Korea from making further provocative moves.
Speaking on the Fox News Sunday program, CIA Director Mike Pompeo said that “there's nothing imminent today" but that it was important to make clear to North Korea that U.S. patience has worn out.
Pompeo said that the United States wants North Korea to understand "that America is no longer going to have the strategic patience that it's had that has permitted him to continue to develop his weapons program. It's that straightforward."