They loathed each other more than death could overcome. Sen. John McCain, Republican of Arizona, who died on Aug. 25 at the age of 81 after battling brain cancer, stood for everything President Donald Trump has set about dismantling: the Atlantic Alliance, toughness toward Vladimir Putin's Russia, a rules-based international order, America's word as solemn pledge in the cause of liberty. Honor, decency and duty were ideas around which McCain built his life of service. They are concepts that have no meaning for Trump.

Held as a prisoner of war for more than five years after being shot out of the sky on his 23rd bombing round over North Vietnam in 1967, McCain knew the extremes of human experience, including torture. This imbued him with a humanity and resolve that transcended politics, even if it did not dim his cantankerous bellicosity. He was a man of conviction. He preferred to be wrong than to bend. Trump, by contrast, was the rich kid from Queens, who avoided the Vietnam draft by finding a doctor who, for a fee, detected bone spurs in his heels. Conscience never stopped Trump, the man without principle.

Trump had called McCain a "dummy." He had called him a "loser." He had said in 2015, while on the campaign trail, that McCain is "not a war hero" because "I like people who weren't captured."

McCain had tried, not always successfully, to take the high road in response to these insults, but his contempt for Trump was clear, not least in these words uttered by the Senator in 2017: "To refuse the obligations of international leadership and our duty to remain 'the last best hope of earth' for the sake of some half-baked, spurious nationalism cooked up by people who would rather find scapegoats than solve problems is as unpatriotic as an attachment to any other tired dogma of the past that Americans consigned to the ash heap of history. We live in a land made of ideals, not blood and soil."

McCain, at his best, was very, very good. He went places of which Trump, in his ahistorical smallness and complete absence of curiosity, is not even aware. So, it was inevitable that the hostility would endure through McCain's demise and that Trump would lose yet another opportunity to show a minimum of dignity. The president tweeted an expression of sympathy to McCain's family but refused repeated requests from senior staff -- including Vice President Mike Pence and John F. Kelly, the White House chief of staff -- to salute McCain in death through a solemn, unifying statement.

Then came the flag fiasco. Trump quickly had the flag atop the White House returned to full staff from half-mast, a decision former President Jimmy Carter called a "very serious mistake." Of course, Trump, whose loud mouth masks his cowardice, backed away. As protests poured in from veterans and a #NoRespect hashtag gained traction on Twitter, the flag was lowered again on Monday. The White House issued a respectful, if scarcely uplifting, statement. President Trump did not attend McCain's memorial service at the Washington National Cathedral on Saturday. Presidents George W. Bush and Obama delivered eulogies. It was simple: McCain did not want this president at his funeral.

A Politician of Principle

Behind the feud lie fundamental differences about America's place in the world. That's what makes the feud important rather than petty. As the Republican Party has folded into the Trump Party in one of the most conspicuous acts of political spinelessness in American history, McCain came to stand almost alone as a politician of principle. His party moved. He did not.

There used to many Republicans like him, people like former Senator Richard Lugar who took seriously the United States commitment to a freer, more open, more democratic world underwritten by American power. They have vanished. The drumbeat of "America First" and of foreign policy as a zero sum game where the American refrain to allies is "Pay up!" continues to rise.

Chancellor Angela Merkel put it well: "John McCain was led by the firm conviction that the sense of all political work lies in service to freedom, democracy and the rule of law. His death is a loss to all those who share this conviction." It was not, of course, a loss to Trump. These convictions are not his. From Saudi Arabia to the Philippines, from North Korea to Russia, Trump has yet to meet a strongman -- and they are all men -- he does not like. Merkel, the product of a democracy forged through United States postwar tutelage, is more problematic.

I disagreed with McCain about many things: his incorrigible itch to bomb Iran (and not only Iran), his reflexive hawkishness, his bizarre back-and-forth on Obama's Affordable Care Act. He ran an almost comically disastrous campaign as the Republican candidate for the presidency in 2008. His choice of Sarah Palin as running mate elevated the kind of jingoistic stupidity that has become a Republican hallmark in the age of Trump. It was a terrible mistake.

Yet even in the midst of that political disaster, McCain showed his character, his capacity to put country before party. When a woman at a town hall meeting in Minnesota suggested his Democratic opponent, Barack Obama, could not be trusted because "he's an Arab," McCain grabbed the microphone to say: "No, Ma'am. He's a decent family man and citizen that I just happen to have disagreements with on fundamental issues." Trump, of course, spent many years trying to prove Obama was not born in the United States, the kind of scurrilous trafficking in lies that has become a distinguishing feature of his presidency.

I wish I could believe that the outpouring of sympathy for McCain marks a turnabout in American politics, the moment when principle will rise above lies, self-sacrifice above self-enrichment, responsibility for human rights above the abdication of American values. I don't, at least in the near term.

The nationalist, nativist, xenophobic tide has not yet run its course. McCain's moving words in his farewell statement to Americans -- that American greatness is weakened "when we hide behind walls, rather than tear them down" -- are true, but tens of millions of anxious Americans are not yet ready to hear them. In many respects, McCain was a dinosaur. The world has lurched on -- and downward.

A Voice for Human Rights Is Gone

In fact, McCain's passing may make it easier for Trump to do his worst on the international front. He used his chairmanship of the Senate Armed Services Committee to challenge President Trump on torture, on immigration, on Putin's Russia and on NATO. When Trump embarrassed himself in Helsinki in July, genuflecting to Putin over Russian interference in the 2016 election, McCain was withering: "No prior president has ever abased himself more abjectly before a tyrant." Such unequivocal stands will be missed.

McCain's ally was Senate Foreign Relations Committee Chairman Bob Corker, Republican of Tennessee, who also tried to rein in Trump's wayward diplomacy and reaffirm the United States' commitment to NATO. Now McCain is gone and Corker will be replaced next year, meaning the president's foremost Republican critics -- almost an oxymoron these days -- have been replaced by Trump loyalists. Do not rule out Trump folly on the North Korean or Iranian front over the next year. I said McCain could be very, very good. Nowhere more so than on the subject of torture, a practice for which Trump's sympathies are evident, and not only in his appointment of Gina Haspel to head the CIA -- a woman deeply involved in the "enhanced interrogation' regime of 2003-2005.

Now here is McCain in 2014, responding to the Senate Intelligence Committee Report on those appalling CIA methods deployed in the aftermath of the 9/11 attacks on the United States: "I know from personal experience that the abuse of prisoners will produce more bad than good intelligence. I know that victims of torture will offer intentionally misleading information if they think their captors will believe it. I know they will say whatever they think their torturers want them to say if they believe it will stop their suffering. Most of all, I know the use of torture compromises that which most distinguishes us from our enemies, our belief that all people, even captured enemies, possess basic human rights, which are protected by international conventions the U.S. not only joined, but for the most part authored."