But despite the escalating tensions, U.S. officials said they have focused more closely on what North Korea is doing than on what it is saying.

“Putting on a show is not the same as taking action,” said a senior administration official, who spoke on the condition of anonymity to discuss the volatile situation. “Describing the situation as akin to war is not to be remotely confused with wanting a war, let alone going to war.”

The senior official and others said that U.S. military commanders are closely watching the situation, which has escalated since North Korea conducted a nuclear weapons test in December. In addition, officials cited new levels of cooperation and mutual confidence between the United States and allies in South Korea and Japan.

While a direct attack on U.S. forces on the mainland or in the Pacific seems unlikely, nongovernment analysts said the rising tensions increase the risk of some form of limited armed conflict. North Korea recently cut off its military phone line with the South, which is used to coordinate logistics along the demilitarized border buffer.