If President Trump hoped to keep North Korea guessing with his latest threats, he has also left many Americans — and perhaps even his own administration — equally puzzled.

Over the weekend, Trump said his predecessors in the White House have talked to North Korea for the past 25 years without success. “Sorry, but only one thing will work!” Trump tweeted Saturday.

“What the heck is that?” said Jeffrey Lewis, an analyst at the Middlebury Institute of International Studies. “You just can’t parse any of it.”

Trump seemed to refer to military action to force a halt to North Korea's nuclear weapons and missile programs, but analysts doubt he is referring to a specific action plan. “I think he is just blustering,” Lewis said.

Trump has repeatedly mocked North Korean leader Kim Jong Un by calling him "Little Rocket Man," one of many personal insults the two leaders have exchanged.

The Pentagon has cautioned that any military action on the Korean Peninsula would be catastrophic, putting millions of civilians at risk. North Korea has artillery and rockets aimed at South Korea's capital, Seoul, just 35 miles from the Demilitarized Zone that separates the two countries. About 25 million people live in Seoul and surrounding suburbs.

Trump's veiled threats raise the risk of miscalculation by leading Kim to think the United States is about to attack, Lewis said. If he feared an attack was imminent, he might order a pre-emptive attack.

“It’s bad signaling because people will fill in the blanks,” Lewis said.

Saturday’s tweet followed equally ominous comments from Trump last week. On Thursday evening with a gathering of top military brass at the White House, he told reporters the group represented the “calm before the storm.” When questioned, he declined to elaborate.

Trump administration officials said there is no confusion over North Korea policy.

Trump's national security adviser, Lt. Gen. H.R. McMaster, said last month the president's comments about Kim have been similar to other American presidents even if the tone is harsher.

McMaster said Trump's remarks have helped clarify how the U.S. would respond to a threat from the North. "I don’t think there is any lack of clarity now,” McMaster said during a conference sponsored by the Institute for the Study of War.

McMaster and other top administration officials say diplomacy remains their priority for dealing with Kim's nuclear threat, but they also said military action remains a viable option.

Critics said Trump's seemingly off-hand remarks and tweets undercut his own administration.

He recently tweeted that Secretary of State Rex Tillerson was wasting his time by trying to talk with the North Korean government. He posted the tweet as Tillerson was in China talking with the country’s leadership about North Korea.

Tillerson and Defense Secretary Jim Mattis have been measured in their remarks about North Korea.

“We have one foreign policy that comes from the State Department and the Department of Defense and then we have another foreign policy that comes from the president’s Twitter feed,” Sen. Chris Murphy, D-Conn., told CNN on Sunday.

Some analysts think Kim won’t misinterpret Trump’s remarks because he doesn’t take them literally.

Kim has a more sophisticated understanding of the United States and the outside world than his late father and former leader Kim Jong Il, said Michael Madden, an analyst at the U.S.-Korea Institute at the Johns Hopkins School of Advanced International Studies.

“I don’t think North Korea is going to miscalculate Trump’s rhetoric," Madden said. “They know not to take it too seriously.”

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