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PHOENIX — U.S. Sen. John McCain (R-Ariz.) said Tuesday that President Donald Trump must tread cautiously when issuing threats to North Korea if he is unprepared to act.

“I take exception to the president’s comments because you got to be sure you can do what you say you’re going to do,” he told KTAR News 92.3 FM’s Mac & Gaydos.

Earlier Tuesday, Trump said North Korea “had best not make any more threats to the United States” or “they will be met with fire and fury like the world has never seen.”

McCain said he would prefer Trump take the advice of former President Theodore Roosevelt in that he should speak softly, but carry a big stick.

“The great leaders I’ve seen don’t threaten unless they’re ready to act and I’m not sure President Trump is ready to act,” he said.

McCain said he did not know if Trump’s threat was serious and may have just been showmanship.

“It’s not terrible in what he said,” the senator said. “It’s the classic Trump in that he overstates things.”

Despite all of North Korea’s blustering, McCain did not think leader Kim Jong Un was truly ready to go to war.

“I think the rotund ruler in Pyongyang is crazy but he’s not ready to go to the brink,” the senator said.

However, McCain said Tuesday’s news that North Korea may have achieved the miniaturization of nuclear weapons and has developed nuclear warheads needs to be taken seriously.

“It scares me as far as its potential is concerned because they have 1,000 rockets aimed at (South Korea capital) Seoul that could set that city on fire,” he said.

The senator said China should step in and order North Korea to step down by threatening economic sanctions.

“They can shut down the North Korean economy in a week,” he said.

Should China fail to act, McCain said the U.S. should impose trade and other sanctions to force it into action.

McCain has long been a vocal critic of North Korea. In March, he labeled Un as a “crazy fat kid” during an interview with MSNBC.

He also claimed Otto Warmbier, a 22-year-old American who was taken prisoner after stealing a piece of propaganda, was murdered by North Korea.

On Tuesday, presidential adviser Sebastian Gorka told KTAR 92.3 FM’s Arizona’s Morning News said he hoped sanctions leveled by the United Nations against the small country on the Korean peninsula would serve their purpose.

“If there’s a chance of dealing with this peacefully, it’s what just happened last weekend,” he said.

The U.N. Security Council voted unanimously Friday to set harsher punishment after North Korea launched two intercontinental missiles in July. The country said the missiles had the distance to reach the United States.

The nuclear aggression from Un has set world leaders on edge. The newer sanctions that further restrict North Korea’s trading could cost the small country $1 billion a year.

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