That’s the feeling toward the Russian strongman from Republican Sen. John McCain, battling cancer at home and about to publish a memoir that dedicates considerable ink to the U.S. understanding of the 2016 election and its messy relationship with Russia from here.

McCain goes on: “Vladimir Putin is an evil man, and he is intent on evil deeds, which include the destruction of the liberal world order that the United States has led and that has brought more stability, prosperity and freedom to humankind than has ever existed in history.”

Read more of the memoir excerpt in The Wall Street Journal.

McCain said his Putin mistrust predates Trump. “I have been an equal-opportunity skeptic of four administrations’ policies toward Russia. I’ve gotten plenty of things wrong in a long political career. Putin isn’t one of them.”

McCain writes that evidence of Russian interference in the 2016 presidential election unsettled him. Even more so, the uncertainty about what a Trump administration might do about it, or not, upset the senator more.

“I had strongly disagreed with candidate Trump’s admiration for Vladimir Putin, which I put down to naiveté and a general lack of seriousness about Putin’s antagonism to U.S. interests and values. I was skeptical that Trump or his aides had actively cooperated with Russia’s interference,” he wrote. “But even a remote risk that the president of the United States might be vulnerable to Russian extortion had to be investigated.”

McCain had agreed to receive a copy of what is now referred to as “the dossier.” A former MI6 officer by the name of Christopher Steele had been commissioned to investigate connections between the Trump campaign and Russian agents as well as potentially compromising information about the president-elect that Putin allegedly possessed. He compiled a salacious dossier, which critics have said has unverified material. The president has questioned if the FBI, of which he’s expressed heavy criticism, paid for its creation.

“I reviewed its contents,” McCain writes. “The allegations were disturbing, but I had no idea which if any were true. I could not independently verify any of it, and so I did what any American who cares about our nation’s security should have done. I put the dossier in my office safe, called the office of the director of the FBI, Jim Comey, and asked for a meeting. I went to see him at his earliest convenience, handed him the dossier and explained how it had come into my possession. I said I didn’t know what to make of it, and I trusted the FBI would examine it carefully and investigate its claims.

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Sen. McCain’s new memoir (written with Mark Salter), “The Restless Wave: Good Times, Just Causes, Great Fights and Other Appreciations,” will be published on May 22 by Simon & Schuster.