Hillary Clinton just made her best case against Donald Trump

Hillary Clinton just took her biggest shot yet at the idea of President Donald Trump.

Thursday afternoon, Clinton gave a speech that was billed as a major foreign address. Indeed, the speech was structured as a traditional campaign policy address, with Clinton laying out her ideas and contrasting them with her opponents’.

But the speech wasn’t really about foreign policy per se. It’s about why Donald Trump, the person, is fundamentally unfit to hold the highest office in the land.

“Donald Trump’s ideas aren’t just different — they are dangerously incoherent,” Clinton said at the beginning of the speech. She continued, with a few lines that really cut to the core of the speech:

They’re not even really ideas: just a series of bizarre rants, personal feuds, and outright lies. He’s not just unprepared, he’s temperamentally unfit to hold an office that requires knowledge, stability and immense responsibility. This is not someone who should ever have the nuclear codes — because it’s not hard to imagine Donald Trump leading us into a war just because somebody got under his very thin skin.

This wasn’t the restrained, diplomatic Clinton we’ve seen for most of the campaign. This was a full-on firebrand, full of righteous rage at the idea that someone like Donald Trump could possibly be president of the United States.

Thursday’s speech, then, wasn’t a narrow foreign policy address. It was Clinton debuting her fundamental case against Trump — one that hit on exactly what makes so many people so uneasy about Trump’s candidacy.

Some of the speech was devoted to Clinton outlining her vision for world affairs — strengthen America’s economy, work with allies, take the fight to terrorists, and the like. But those aren’t really the focus: Her discussion of her own ideas is brief, and her attacks on Trump took up the bulk of the speech.

After Clinton briefly summarizes her plan to fight ISIS — intensify the bombing campaign, create a safe zone in Syria — she pivots straight to attacking Trump’s claim that he has a “secret” plan to fight ISIS:

What’s Trump’s? He won’t say. He is literally keeping it a secret.

The secret, of course, is he has no idea what he’d do to stop ISIS.

Likewise, when she talked about the need to work with allies, she highlighted Trump’s proposal to withdraw from our security alliance with Japan if it doesn’t start paying the US money and tell the country to get nukes instead:

It’s no small thing when he suggests that America should withdraw our military support for Japan, encourage them to get nuclear weapons, and said this about a war between Japan and North Korea – and I quote – “If they do, they do. Good luck, enjoy yourself, folks.”

I wonder if he even realizes he’s talking about nuclear war.

That language in the last sentence — “I wonder if he even realizes” — is the key to understanding this speech. Clinton’s argument, over and over again, is that Trump literally does not understand the policy issues at stake, and thus blithely proposes policies that would end up doing massive harm without even understanding it.

“He says he doesn’t have to listen to our generals or ambassadors, because he has – quote – ‘a very good brain,’” she argued. “He also said, ‘I know more about ISIS than the generals do, believe me.’ You know what? I don’t believe him.”

This isn’t an attack on any one specific policy ideas; as Clinton said at the beginning of the speech, she doesn’t see Trump as really having ideas. Rather, it reflects Trump’s lack of basic understanding about the way the world works.

That’s why her attacks went beyond foreign policy, attacking Trump’s comments on the debt and deficit as examples of his dangerous ignorance.

“He believes we can treat the US economy like one of his casinos and default on our debts to the rest of the world, which would cause an economic catastrophe far worse than anything we experienced in 2008,” Clinton said. “Those are the words, my friends, of someone who doesn’t understand America or the world.”

The point here isn’t just to attack Trump’s ideas, as you would a normal candidate. It’s to delegitimize Trump entirely: to say that he lacks even the most basic of basic qualifications to be president of the United States.

Theoretically, Trump could rectify his policy ignorance over the course of the campaign. He could study up on foreign policy and reverse his scariest policy positions. Indeed, he has a habit of changing his proposals, sometimes outright lying about what he’s said in the past.

So Clinton’s case against Trump cuts deeper than just highlighting some bad policy ideas. She argues that he is temperamentally incapable of being a good president: that the kind of person he is could never, ever make good decisions as president.

This is a point she hammers home toward the end of the speech, when she tries to get the audience to imagine what Trump would be like if he were actually president:

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 children into battle. Imagine if he had not just his Twitter account at his disposal when he’s angry, but America’s entire arsenal.

Do we want him making those calls – someone thin-skinned and quick to anger, who lashes out at the smallest criticism?

The point here isn’t about specific policies, or even comments. It’s about the general way Trump has behaved himself: volatile, self-absorbed, thin-skinned. These qualities, Clinton argues, are what give rise to his terrible foreign policy proposals.

Clinton takes aim, for example, at Trump’s positive comments about dictators in Russia, China, and North Korea. “He said, ‘You’ve got to give Kim Jong Un credit’ for taking over North Korea – something he did by murdering everyone he saw as a threat, including his own uncle, which Donald described gleefully, like he was recapping an action movie,” she recounts.

These aren’t just random comments, Clinton says — they are windows into a broken psyche. She more or less literally tells Trump to seek psychiatric help rather than the presidency:

I’ll leave it to the psychiatrists to explain his affection for tyrants. I just wonder how anyone could be so wrong about who America’s real friends are. But it matters. Because if you don’t know exactly who you’re dealing with, men like Putin will eat your lunch.

This is strong language for a presidential race, and it reflects Clinton’s basic strategy of delegitimizing Trump. She’s trying to cast him as not just worse than a normal Republican but as a threat to the republic that everyone, on both sides of the aisle, should see as unacceptable.

What makes this speech so strong — and so much better than the kind of weak attacks the Clinton camp has floated recently — is that Clinton has really put her finger on the reasons people around the country are worried about Trump.

It’s true that Trump knows nothing about foreign affairs. It’s true he has blithely proposed dangerous ideas, like conquering Iraq and stealing its oil. It’s true he says bigoted things. It’s true he is a volatile person, that he’s demonstrated over and over again that he acts wildly based on petty grievances.

These are the things that make Trump qualitatively different from any past presidents, who at least had a kind of experience that made them into known and somewhat predictable quantities. They’re why Trump has the highest unfavorable ratings of any major party candidate for the presidency, and why the Economist ranks a Trump presidency as one of its top 10 risks to the world this year.

Clinton wants to highlight this: to make the core of her message that Trump isn’t a normal Republican, but rather someone who’s the most dangerous presidential nominee in recent memory. It’s a very strong choice.