The Editorial Board

USA TODAY

In his incendiary and increasingly unhinged campaign for the presidency, Donald Trump has, by one count, disparaged more than 270 people, places and things.

His targets have included Mexican immigrants, Muslims, Fox News anchor Megyn Kelly, Iowans, Belgians, Republican House Speaker Paul Ryan,Republican Sen. John McCain, Pope Francis, German Chancellor Angela Merkel, China, Japan, The New York Times, fellow billionaire Mark Cuban and, as of Sunday morning, Saturday Night Live.

Conspicuously absent from the list: Russia and its remorselessly autocratic and self-aggrandizing leader, Vladimir Putin. For reasons that are mystifying to national security experts, fellow politicians and U.S. allies, Trump continues to defend both.

At the presidential debate on Oct. 9, just two days after national intelligence director James Clapper formally accused Russia of hacking into computers at the Democratic National Committee, Trump asserted there was no evidence that Russia was involved. He even questioned whether any hacking had taken place.

Also in the debate, and on many other occasions, Trump defended Russia’s actions in Syria even as it unleashes a torrent of carnage and supports the bloodthirsty regime of President Bashar Assad. Trump defends this position by saying that Russia is killing Islamic State terrorists. The main problem with this argument is that Russian forces are killing other opponents and innocent civilians at a much faster clip.

Trump’s instincts are correct: Opposing view

Since receiving the Republican nomination, Trump has received two national security briefings. Almost certainly, these included assessments of Putin’s sinister actions and intentions. Yet Trump continues to be an apologist for Putin. What gives?

No one besides Trump seems to know for sure, but among the plausible explanations:

He might have undisclosed financial interests that depend of the backing of the Russian government. Trump's tax returns could shed light on whether this is the case, but he refuses to release them.

His foreign policy is based on a calculus of pure vanity — namely, that he supports people who compliment him, as Putin has, and attacks those who criticize him.

He genuinely admires Putin's authoritarian-thug approach to leadership and sees him as a model for his own governance, should he be elected.

To just about everyone except Trump, Putin presents a clear threat to the security of America and its allies. His goal is to destabilize Western Europe while reassembling much of the old Soviet Union and its Warsaw Pact alliances to their former glory. He has systematically quashed dissent at home, and hackers associated with his regime appear to be engaged in an unprecedented effort to tamper with U.S. elections.

Trump's latest reckless ramblings about the elections being "rigged" by the news media and at the polls play right into the Kremlin's effort to undermine faith in the legitimacy of American democracy. If Trump can’t, or won’t, see the problem that Russia poses for the United States, he has no business being the nation's commander in chief.

USA TODAY's editorial opinions are decided by its Editorial Board, separate from the news staff. Most editorials are coupled with an opposing view — a unique USA TODAY feature.

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