MOSCOW — In a combative essay published Thursday in the online newspaper Pravda.ru, Senator John McCain, Republican of Arizona, declared himself to be “pro-Russian” but delivered a blistering attack on President Vladimir V. Putin, describing him as presiding over a failed petro-state and as a quasi dictator who rules “by corruption, repression and violence.”

Mr. McCain’s article was intended to answer an Op-Ed column by Mr. Putin in The New York Times on Sept. 12 that made the case against President Obama’s threatened military strike on Syria. Mr. Putin’s column, in which he presented Russia’s position as defending international law and respect for state sovereignty, generated fierce debate, including praise and accusations of hypocrisy.

While Mr. Putin’s article focused more generally on American foreign policy, Mr. McCain, who has long been a sharp critic of the Kremlin, focused squarely on the Russian president himself. In his introduction, though, Mr. McCain made an effort to dispel the idea that he is anti-Russian, a perception that is widespread here.

“I am not anti-Russian,” Mr. McCain wrote. “I am pro-Russian, more pro-Russian than the regime that misrules you today.”