"(Kim Jong-un) fundamentally believes the only way he survives is to have nuclear weapons," Sherman told David Axelrod on "The Axe Files," a podcast from the University of Chicago Institute of Politics and CNN. "The world has to show him that it is a choice between those weapons and survival."
Noting that the North Korean leader might use nuclear weapons "if he felt his back was up against a wall," Sherman warned that the failure to come to a diplomatic solution could risk a catastrophe of "unimaginable" consequences.
"No president, Democrat of Republican, has deployed all of our tools all at once to really take a crack at this problem," Sherman said, before listing a number of options that could be pursued, including increased sanctions, heightened military and intelligence efforts, and a diplomatic strategy that includes a tougher posture from China.
North Korea has increased its missile activity of late, including numerous launches in March alone. President Donald Trump remarked to reporters earlier this week that Kim Jong-un was "acting very, very badly," and he pressured China in a recent tweet for having "done little to help" defuse the situation. And Secretary of State Rex Tillerson just returned from a trip to Asia
in which he told our allies that "all options are on the table" regarding North Korea.
But Sherman went on to express "very little" confidence in the Trump administration's ability to navigate the "high-risk" diplomacy required of this issue. She predicted that the administration's delay in appointing top staff at the State Department, as well as its intention to significantly cut the agency's budget, will limit America's ability to conduct diplomacy.
She also said the situation has been made more difficult by Trump's tendency to speak carelessly or allege false information, which has weakened American leadership around the world and undermined the presidency.
"Because President Trump has lost such credibility, and he says so many outrageous things all of the time, no one hears him with the same ear," she said.
To hear the whole conversation with Sherman, click on http://podcast.cnn.com
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