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The reviews of Donald Trump's grand foray into foreign policy agreed on one thing, which is that Trump can't even agree with himself. His Wednesday speech was an exercise in self-contradiction, a feast of incoherence, a walk up the down escalator.

He pledges to be the best of friends but threatens to abandon alliances. He wants America to shun nation building but create stability. He plans to spend more money but waste less.

He vows to be consistent but unpredictable. He intends to restore respect, even as people around the world lower their opinion of America a bit more every day he remains in the race.

How does Trump reconcile his incompatible promises and implausible visions? He doesn't, and he's never tried. Inconsistency is not a defect in the product; it is the product. His supporters don't hold his carefree contradictions against him. Some don't care, and some embrace them.

The speech also rested on claims that are not actually true -- that Iran has violated the nuclear agreement, that the Islamic State is getting rich selling Libyan oil, that he was "totally against" the Iraq War, that President Barack Obama "made (Iran) a great power in the Middle East." It contained his usual array of promises of what he would do as president, unsupported by specifics on how he would do them.

Factual accuracy and logic are no more important to Trump's followers than to him. They believe what they feel, not what they can prove. They refuse to let reality undermine their firm convictions. They assume that Trump's bold talk and iron resolve will turn every obstacle to dust.

On foreign policy, Trump indulges popular whims that would have trouble coexisting in the real world: Destroy the Islamic State but avoid getting bogged down in the Middle East. Punish the Chinese on trade but get them to control North Korea. Keep out Muslims while "working very closely with our allies in the Muslim world" to stop terrorism.

The address is just the latest symptom of his unwillingness to make choices or even acknowledge that choices must be made. He specializes in telling people what they want to hear, even if it doesn't come close to making sense.

This is the guy who plans to build the most expensive wall in history without asking a dime from the taxpayers -- by forcing Mexico to bear the cost. He wants to bring back manufacturing jobs that we've lost, ignoring that most of them disappeared because of advances in technology and improvements in productivity, not foreign competition.

Trump proposes spending money to rebuild infrastructure, upgrade the military and preserve Social Security just as it is. He would boost federal expenditures by 3 percent of gross domestic product, according to the bipartisan Committee for a Responsible Federal Budget. That would boost outlays by more than $500 billion per year.

Meanwhile, his fiscal plan would slash taxes on both corporate and individual income. These cuts would shrink federal revenue by more than $10 trillion over a decade, the nonpartisan Tax Foundation calculates.

On top of all this, he told The Washington Post that he would eliminate the entire $19 trillion national debt in just eight years -- a claim so ridiculous he soon had to retreat. He said instead that he would merely "reduce" the debt.

Even that assertion can't be taken seriously. The stark, simple fact is that his budget proposals would do just the opposite -- with a vengeance. It is impossible to reduce revenue, increase spending, widen the budget deficit and pay down the debt. Any Wharton School graduate knows as much.

But Trump also knows what a lot of Americans want to hear, on foreign affairs as well as domestic ones. What they don't want to hear is that making sensible government policies means choosing among painful trade-offs.

These voters want everything they now get in the way of federal benefits while paying less in taxes. They want the United States to dominate the world and get its way without fail, but they shun any personal sacrifices to achieve those ambitious goals.

Trump is not one to disabuse them of these pleasant assumptions. If they insist on believing they can have it all, he'll promise to give it to them.

If he ends up in the White House, they'll be terribly disappointed to learn it was too good to be true. Until then, they'll enjoy the fantasy.