The final debate between Democratic presidential candidate Hillary Clinton and her Republican rival Donald Trump on the night of Oct. 19 reminded most Americans why only one of them is fit to be president.
Fundamentally, that judgment has nothing to do with their policy positions and everything to do with the fact that Trump refused to commit to honoring the results of the election should he lose.
Trump's mission going into this debate was to broaden his appeal, including by sounding reasonable and promising to deliver real change to the large majority of Americans who believe that their country is on the wrong track.
Instead, he demonstrated that his self-regard is even greater than his regard for the people's choice on Nov. 8 -- to the point that he may reject the election outcome, potentially leading the U.S. into constitutional crisis. Whether one is a Republican or a Democrat, such a position is indefensible.
In this debate, Clinton looked and sounded like a president. On foreign policy, she positioned herself to the right of President Barack Obama -- proposing robust policies to end the crisis in Syria and defending the value of America's overseas alliances. She also took a firmer line with respect to America's competitors, who appear to be using the waning months of Obama's term to make strategic gains at overall expense to his country.
Clinton called out Russia's unprecedented efforts to influence the U.S. election outcome through leaks of internal Clinton campaign documents and demanded that Trump repudiate them. When he instead promised to pursue better ties with President Vladimir Putin, she interjected that Putin would "rather have a puppet as president," in the form of her rival. "You are willing to spout the Putin line, ... break up NATO, do whatever he wants. ... We've never had a foreign government trying to interfere in our election."
When Trump attacked Clinton for favoring trade agreements like the Trans-Pacific Partnership, she retorted that, in 1987, he had pursued an advertising campaign criticizing then-President Ronald Reagan for his trade policy in the face of a then-rising Japan. "We are the laughingstock of the world" on trade, Trump had charged at the time, as Clinton reminded her audience.
Republicans around the country are still suffering whiplash: The Republican presidential candidate was defending Putin even as Clinton lambasted appeasement of Russia, and attacking Reagan even as the Democratic nominee defended his legacy.
Clinton also poked Trump for encouraging U.S. allies including Japan and South Korea to acquire nuclear weapons to defend themselves.
With respect to the U.S.-Japan alliance, Trump charged, "We are being ripped off. ... They have the bargain of the century" by falling under the U.S. nuclear defense umbrella. "Why are we protecting them? We're protecting people. They have to pay up."
America cannot afford to defend Japan and other allies, he remarked -- showing no awareness that it is actually cheaper to station American forces in these countries, and that forward-deploying U.S. troops to safeguard peace is exponentially cheaper than fighting in wars produced by the instabilities that could result from U.S. withdrawal.
Clinton highlighted the grave risks inherent in Trump's approach. "Telling our allies to undertake nuclear competition in Asia is dangerous. The United States has kept the peace through our alliances -- which make the world safer and ... the United States safer."
Trump's solutions to the country's ills -- erecting barriers to both people and trade, undercutting U.S. alliances and reassuring American adversaries like Putin -- are unpalatable to a solid majority of American voters.
With only three weeks left in this campaign, a key question is whether Trump will lose in ways that allow the Republican Party to make a fresh start through its leadership in Congress, or whether Trump's defeat will drag Congressional Republicans down with him, creating a new Democratic imperium.
As president, Clinton will need a Republican Congress to increase defense spending in order to resource the long-term U.S. rebalance to Asia that she championed as secretary of state. She will need a Republican Congress to support the TPP, even if her administration renegotiates elements of that deal (as Obama did with the Korea-U.S. Free Trade Agreement, which he inherited from President George W. Bush).
DEMOCRATIC DIFFICULTIES Should Donald Trump's likely electoral collapse on Nov. 8 lead to a Democratic sweep of the U.S. Senate and House of Representatives, which are now in Republican hands, Clinton will have greater difficulty enacting her Asia policy agenda.
Rather than moving to the middle to cut grand bargains with Congressional Republican leaders on domestic reforms, defense and trade, she will be pulled to the left by the socialist wing of the Democratic Party, led by figures like former presidential candidate Bernie Sanders and Sen. Elizabeth Warren.
Clinton is a centrist who, on foreign policy and trade issues, in many ways leans Republican. But her overseas priorities will not be those of her party, which is less internationalist.
The Republican nightmare is not that Trump loses -- he deserves to, on his own merits -- but that he takes the current Republican majorities in Congress down with him, further damaging his party's fortunes.
Should they hold on to control of Congress, Republican leaders like House Speaker Paul Ryan and Sen. Marco Rubio must rebuild their party around principles radically different from those espoused by Trump -- which will be much easier to do if they remain in charge and he suffers a landslide defeat that discredits his protectionism and unilateralism.
A President Clinton must then be wise enough to work with like-minded Republicans and Democrats in Congress on a foreign policy agenda that overcomes the legacies of both Trump's nativism and Obama's retrenchment of American power.
The world beyond America's borders is not simply a source of danger but one of fabulous opportunities to advance prosperity and security, if the U.S. can return to its bipartisan tradition of foreign policy leadership.
Daniel Twining is a director at the German Marshall Fund of the U.S., a former official of the George W. Bush administration and a veteran of six presidential campaigns.