Susan Rice: Trump is approaching a 'very real challenge' with North Korea

Susan Rice, the former US national security adviser who served in the Obama administration, said this week's verbal tug-of-war between President Donald Trump and North Korean dictator Kim Jong Un is proof that Trump faces a "very real challenge" confronting the unpredictable regime.

"When the president of the United States makes statements that could be mistaken for Kim Jong-Un's, I think that rattles our allies enormously and it risks a miscalculation on the North Korean side," Rice told CNN's Wolf Blitzer on Thursday.

Rice was referring to comments Trump made from his Bedminster, New Jersey, golf club on Tuesday, where he declared North Korea would feel "fire and fury like the world has never seen" if it kept threatening the US. The remarks immediately conjured among many in the US visions of a full-scale nuclear war. Kim Jong Un, seeming to draw the same conclusion, promptly responded with another threat - this time against the US territory of Guam.

"We need to be very measured, very careful, very planned in our rhetoric. I hope that we will see more measure out of the administration and out of the president as he approaches this very real challenge," Rice said.

When asked whether the US could contemplate a preemptive attack on North Korea, the former national security adviser and ambassador to the United Nations said the outcome would be "catastrophic" for the Korean Peninsula, and put the US at risk of a direct confrontation with China, North Korea's closest ally.

"A pre-emptive attack by the United States would be a very, very poor choice, a very dangerous choice," Rice said, adding a warning for Kim Jong Un's regime: "The North Koreans understand that if ever they were to use their nuclear weapons against the United States or our allies, they would face annihilation."

Despite bipartisan lamentations about the perceived loss of measured diplomacy between the US and North Korea this week, experts have argued an actual nuclear conflict is unlikely. As Business Insider's Alex Lockie reported on Wednesday:

"Trump didn't call for a strike, and he won't. Neither will Kim Jong Un. Both men will get acceptable outcomes without firing a shot."