Heidi M. Przybyla

USA TODAY

Hillary Clinton delivered a fiery rebuke of Donald Trump as someone who is "temperamentally unfit" to serve as commander in chief with "dangerously incoherent" foreign policy ideas in an address Thursday that argued his candidacy poses a threat to the nation's security and could even lead to a global economic crisis.

Clinton listed a series of policies that Trump has espoused as part of an extensive broadside, including threats to withdraw from the North Atlantic Treaty Organization, his proposal to temporarily ban non-citizen Muslims entering the United States, suggesting countries like Saudi Arabia should have nuclear weapons and for praising "dictators" like Russian leader Vladimir Putin and sanctioning torture as an interrogation method.

"Donald Trump's ideas aren't just different. They are dangerously incoherent. They're not even really ideas, just a series of bizarre rants, personal feuds and outright lies," Clinton said during the speech in San Diego. "He is not just unprepared, he is temperamentally unfit to hold an office that requires knowledge, stability and immense responsibility."

The speech is her first major foreign policy address since Trump clinched the GOP nomination and comes as she battles Vermont Sen. Bernie Sanders ahead of the June 7 California Democratic primary in her bid to lock down the Democratic presidential nomination.

Her Thursday remarks are part of a broader narrative the Clinton campaign is pursuing that goes after Trump’s character and temperament in painting him as unfit to lead the nation. Clinton said Trump is someone who should never have access to the nation's nuclear weapons codes as part of a harsh critique of Trump's policy positions that many of his GOP challengers shied away from during the nomination fight.

"It's not hard to imagine Donald Trump leading us into a war just because someone got under his very thin skin," said Clinton.

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The speech contrasted Trump’s positions and rhetoric with her vision for keeping the nation safe, drawing heavily on her experience as secretary of State as Clinton seeks to balance her attacks with a more positive message about her own agenda.

"Don't let anyone tell you that America isn't great. Donald Trump's got America all wrong," said Clinton. "We are a big-hearted, fair-minded country."

"This election is a choice between two very different visions of America: one that's angry, afraid and based on the idea that America is fundamentally weak and in decline. The other is hopeful, generous and confident in the knowledge that America is great, just like we always have been."

In response, Trump took to Twitter, saying: "Bad performance by Crooked Hillary Clinton! Reading poorly from the teleprompter! She doesn't even look presidential!"

Recent NBC/Wall Street Journal polling shows Clinton is hitting Trump from a position of relative strength when it comes to foreign policy matters.

While Trump has a big lead over Clinton on changing business as usual in Washington and dealing with Wall Street, Clinton has a nearly 30-point lead over Trump on handling foreign policy. She has a 10-point lead on who would be the better commander-in-chief, the latest survey found, while Trump has about the same advantage over Clinton on handling trade issues and the economy.

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"Making Donald Trump our commander in chief would be a historic mistake" said Clinton, adding that it would undo the work both parties have done over decades to strengthen the nation's defenses. "Imagine Donald Trump sitting in the situation room making life-or-death decisions on behalf of the United States, imagine him deciding whether to send your spouses or children into battle," said Clinton.

Her wide-ranging critique also included mentions of Trump’s insistence that climate change is a hoax created by the Chinese, his statements that Sen. John McCain, a former Vietnam prisoner of war, is not a hero, and that the U.S. military is “a disaster,” as well as his squabbles with the leaders of U.S. allies from Britain, Germany, Mexico and even the Pope.

At times she poked fun at him, including Trump's previous comments that he has “a very good brain” and knows “more about ISIS than the generals do.” She also cited his insistence that he has foreign policy experience because he ran a Miss Universe pageant in Russia.

At one point, she even said that a “Trump presidency could lead to a global economic crisis,” citing his willingness to default on the U.S. debt and “bizarre fascination with dictators and strong men who have no love for America.”

“I will leave it to the psychiatrists to explain his affection for tyrants,” said Clinton. “I just wonder how anyone could be so wrong about who America’s real friends are,” adding “men like Putin will eat your lunch.”

In touting her own record, Clinton described her involvement in President Obama’s decision to kill al Qaeda leader Osama bin Laden, "wrestling" with the Chinese over a climate change deal, her role in brokering a Middle Eastern cease fire and negotiating a deal to reduce Russia’s nuclear arsenal.

For his part, Trump has been trying to undercut her résumé by questioning her judgment over the invasions of Libya, which took place during her tenure as secretary of State, and Iraq, which she voted for as a U.S. senator from New York.

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On Thursday night, Sanders sent out a statement on Clinton's speech focusing on what he sees as weakness in her record.

"I agree with Secretary Clinton that Donald Trump's foreign policy ideas are incredibly reckless and irresponsible," Sanders said. "But when it comes to foreign policy, we cannot forget that Secretary Clinton voted for the war in Iraq, the worst foreign policy blunder in modern American history, and that she has been a proponent of regime change, as in Libya, without thinking through the consequences."