Democratic presidential nominee Hillary Clinton on Tuesday targeted her Republican rival Donald Trump for being a man who can be provoked easily and should not have "his fingers near the nuclear codes", indicating that the real-estate tycoon is not fit to be the next US President.
The 68-year-old former secretary of state said Trump's "cavalier" attitude about nuclear weapons, the number one threat in the world, is "deeply troubling" as she assured US allies that if elected, her administration would stand behind the country's commitment to them.
"So a man who can be provoked by a tweet should not have his fingers anywhere near the nuclear codes, as far as I think anyone with any sense about this should be concerned," Clinton said in response.
"His cavalier attitude about nuclear weapons is so deeply troubling. That is the number-one threat we face in the world. And it becomes particularly threatening if terrorists ever get their hands on any nuclear material," a combative Clinton said during the first of the three presidential debate here.
Clinton also slammed Trump for his alleged rhetoric on nuclear weapons.
"What we heard Donald say about nuclear weapons. He has said repeatedly that he didn't care if other nations got nuclear weapons, Japan, South Korea, even Saudi Arabia. It has been the policy of the US, Democrats and Republicans, to do everything we could to reduce the proliferation of nuclear weapons.
Trump said, "...I agree with her on one thing. The single greatest problem the world has is nuclear armament, nuclear weapons, not global warming, like you think and your president thinks."
"Nuclear is the single greatest threat. Just to go down the list, we defend Japan, we defend Germany, we defend South Korea, we defend Saudi Arabia, we defend countries. They do not pay us. But they should be paying us, because we are providing tremendous service and we're losing a fortune," he asserted.
Responding to a question Trump ruled out taking out nuclear option off the table.
"We have to be prepared. I can't take anything off the table. Because you look at some of these countries, you look at North Korea, we're doing nothing there. China should solve that problem for us. China should go into North Korea. China is totally powerful as it relates to North Korea," he said and described the Iranian nuclear agreement as the worst deal.
Clinton used the occasion to reassure the American allies.
"Words matter. Words matter when you run for president. And they really matter when you are president. And I want to reassure our allies in Japan and South Korea and elsewhere that we have mutual defence treaties and we will honour them. It is essential that America's word be good," Clinton said.
Besides nuclear weapons, Clinton also said that cyber security and warfare will be one of the biggest challenges facing the next president.
"I think cyber security and cyber warfare will be one of the biggest challenges facing the next president. But increasingly, we are seeing cyber-attacks coming from states, organs of states. The most recent and troubling of these has been Russia," she said.