(AP) -- Hillary Clinton said Friday it was time for a "rethinking" of America's strategy for North Korea following the regime's latest test of a nuclear weapon. Donald Trump and his campaign chief, meanwhile, refused to outline the Republican presidential candidate's plans for defusing tensions on the Korean Peninsula.

The New York billionaire, however, vowed to deploy military muscle to attack America's enemies if provoked.

Largely ignoring North Korea, he noted a recent incident in which he said Iranian ships were "toying with" an American destroyer near the Strait of Hormuz. During a Trump presidency, he promised at a Friday night rally in Pensacola, Florida, ships trying to provoke the U.S. "will be shot out of the water."

In New York, Clinton was focused on the North Korean threat after meeting with a bipartisan group of national security experts.

The former secretary of state said she would seek to impose tougher sanctions on the communist nation, arguing the latest test provides an opening to pressure China, which has been tepid in its response to North Korea's nuclear ambitions.

"I think we have an opening here that we haven't had for the last several years that I intend to do everything I can to take advantage of," Clinton said.

Clinton spoke hours after Trump campaign manager Kellyanne Conway, pressed repeatedly on Trump's plans for the region, said only, "He wouldn't do what's being done now."

"He's not going to reveal all of his plans and he's made that very clear. And maybe someone can ask him in a debate," Conway told "CBS This Morning." ''But the fact is that this entire world would be put on notice that there's a strong leader in the White House."

North Korea's latest atomic test was its fifth, and the second in eight months. South Korean President Park Geun-hye said the detonation, which Seoul estimated was the North's biggest ever in explosive yield, was an act of "fanatic recklessness" and a sign that leader Kim Jong Un "is spiraling out of control."

President Barack Obama condemned the test and said the U.S. would never accept the country as a nuclear power.

In appearances in Florida and Washington, Trump used the North Korean development to attack Clinton. "North Korea, like so many other things, is one more Hillary Clinton failure," he said in Pensacola.

He did not say whether he had a plan to address North Korea's claim the test will allow it to build an array of stronger, smaller and lighter nuclear weapons.

He focused instead on attacking Clinton's credibility. He said Clinton was being "protected" during the Justice Department's investigation into her use of a private email server while secretary of state.

"She could walk right into this arena right now and shoot somebody with 20,000 people watching, right smack in the middle of the heart, and she wouldn't be prosecuted," Trump said.

Meanwhile, Clinton said the United States would not let North Korea pursue a nuclear weapon and said that as president, she would seek new sanctions and work closely with allies in the region, such as South Korea and Japan.

But she also said she would consider discussions similar to recent negotiations with Iran over its nuclear program, because sanctions "aren't enough."

The development in North Korea comes at the end of a week in which Trump and Clinton clashed repeatedly over national security.

The New York billionaire attacked Clinton's record as the nation's chief diplomat, yet he faced criticism from within his own party for refusing to outline his plans for combating foreign policy challenges, including threats posed by the Islamic State group. Trump said this week that he does indeed have a plan, but would convene military leaders in his first 30 days in office to craft another plan.

Trump has also faced criticism for praising Russian President Vladimir Putin during a high-profile national security forum earlier in the week, and appearing on a Russian-backed television network Thursday evening.

On Friday, Clinton said she was "disappointed" by Trump's decision to appear on RT America, saying that "every day that goes by this just becomes more and more of a reality television show. It's not a serious presidential campaign."

With several prominent Republican national security officials already concerned about Trump's national security acumen, Clinton has tried to cast herself as the better potential commander in chief. She has aggressively promoted her growing list of military endorsements from both parties.

On Friday, her campaign said the number of retired generals and admirals endorsing Clinton for president has grown to 110. Trump quickly countered by saying his list had ballooned to 120 former U.S. generals and admirals earlier in the week.

Trump's running mate, Indiana Gov. Mike Pence, received his first intelligence briefing Friday. The vice presidential nominee declined to offer any specifics since the information was classified.

Continuing her aggressive fundraising push, Clinton appeared at two fundraisers in New York. One of them was an LGBT event featuring Barbra Streisand.

Clinton is getting some help from another wealthy backer as well. Billionaire Facebook co-founder Dustin Moskovitz said Friday he's giving $20 million to help defeat Trump.

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Lucey reported from New York. Associated Press writer Julie Bykowicz contributed to this report.

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