McMaster's out. Bolton's in. Be very afraid. New national security adviser is a big fan of using military force: Our view

The Editorial Board | USA TODAY

As if the Trump presidency hasn't created enough causes for concern, here's the latest: A president who famously threatened to rain "fire and fury" down on North Korea has hired one of the nation's most hawkish foreign policy experts as national security adviser.

Former United Nations ambassador John Bolton might very well reinforce Trump's most hard-edged impulses, among them exiting the Iran nuclear deal, in which Tehran agreed to dismantle its nuclear program in return for the lifting of economic sanctions.

Add to this equation the voice of Mike Pompeo, the hard-line CIA director recently nominated to replace the fired Secretary of State Rex Tillerson, and the three-year-old Iran deal's days appear to be numbered.

TOM COBURN: Bolton the right choice for the job

U.S. withdrawal from the multilateral agreement with Europe, Russia and China is likely to prompt Iran to restart its nuclear weapons program, spawning the regional nuclear arms race that Bolton, years ago, wrongly predicted would be the result of President Obama's negotiations with Tehran.

Moreover, withdrawing from the Iran deal would seriously undermine U.S. credibility. Why would North Korean leader Kim Jong Un give up his nuclear weapons in a negotiated agreement — as Iran did in 2015 — if an American president can come along later and arbitrarily tear it up?

So the world might soon face two heated, nuclear crises at once: one in Iran and another in North Korea. Never fear. Bolton — whose belligerent policy ideas were too much even for a Republican-led Senate in 2005, which voted down his nomination as U.N. ambassador (he served temporarily as a recess appointment) — has already opined on what the United States should do about Iran and North Korea: attack.

It's ironic that Trump, a harsh critic of the 2003 Iraq War, would hire an architect and chief defender of the calamitous U.S.-led invasion, which killed hundreds of thousands, created a regional power vacuum that Iran rushed to fill, and spawned the rise of the Islamic State terrorist organization.

Bolton is smart, knowledgeable about world affairs, a skilled bureaucratic infighter — and a big fan of military force. He advocated airstrikes against Iran nuclear sites in 2015: "The United States could do a thorough job of destruction." And the same last month in outlining a legal justification for pre-emptively attacking North Korea: "It is perfectly legitimate for the United States to respond to ... North Korea's nuclear weapons by striking first."

Estimates of the dead in South Korea should such a first strike spiral out of control have ranged as high as 300,000 in the first few days. Trump, in one of his frequent reversals, suddenly declared this month he would meet face-to-face with Kim, and Friday he told reporters that some level of early agreement is "very close to being finalized."

Bolton, whose appointment does not require Senate confirmation, has scoffed at North Korea engaging in honest negotiations. What happens if such talks fail?

Until recently, a triumvirate of White House national security leaders served as necessary guardrails for Trump's fire-and-fury tendencies: Tillerson, national security adviser H.R. McMaster and Defense Secretary James Mattis.

Now Tillerson and McMaster are heading out the door. "God help us if we lose Jim Mattis," James Stavridis, the former NATO supreme allied commander, told MSNBC on Friday. It's a frightening thought.

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