WHEN HE TOOK office as Russian president for a third term in May, there was a bit of uncertainty about the course Vladimir Putin would choose. The streets were packed with angry protesters. Might he take a modernizing path, or would he stick to the authoritarian prickliness of his earlier years as president?

Each week, Mr. Putin demonstrates anew that he is locked in his old ways. In response to the demonstrations, he rammed through legislation sharply increasing fines for violation of the public order. Then came a law requiring nongovernmental organizations that get money from abroad and engage in political activity to register as “foreign agents.” Opposition leaders were harassed.

Now comes a sign that Mr. Putin is preparing to turn his back on his onetime protégé, Prime Minister Dmitry Medvedev, who served as president in between Mr. Putin’s terms. The iPad-toting Mr. Medvedev had come to symbolize hopes for a more open and liberalizing Russia. But the “tandem,” as his partnership with Mr. Putin was once called, seems to be unraveling.

The latest evidence is a video posted Aug. 5 on YouTube. No one knows exactly who made the video, part of a longer film titled “A Lost Day,” but the message is unvarnished: Mr. Medvedev was a coward at the outset of war with Georgia in 2008, when he was president. The criticism comes from, among others, a former chief of the general staff, Yuri Baluyevsky, a retired general who says Mr. Medvedev dithered and refused to give the proper orders until Mr. Putin delivered a “kick” in the pants. At the time, Mr. Putin was prime minister and attending the Olympic Games in Beijing.

Mr. Baluyevsky is biased; he was forced into retirement by Mr. Medvedev before the war. But after the clip appeared, Mr. Putin dignified it with a public response. Mr. Medvedev has repeatedly insisted he acted alone in the early hours of the Georgia conflict. But Mr. Putin flatly contradicted him, saying that he telephoned Mr. Medvedev twice from the Olympics to discuss the war. The implication is that Mr. Putin had to tell him what to do. Mr. Putin is attempting to demonstrate — should there be any doubts — who is the tough guy.

In his remarks about the video, Mr. Putin also reignited the long dispute about who started the war. Russia says that Georgia started shooting first. Georgia says that Russia provoked the conflict. Putin acknowledged approving a war contingency plan for Georgia in 2007, a year before hostilities began. He also confirmed that Russia trained separatist fighters in the breakaway enclave of South Ossetia, where the conflict first broke out, while also stationing peacekeeping forces there. While Mr. Putin’s remarks settled nothing, he seemed to be saying that Russia was eager and ready to give a bloody nose to Georgia, which had become a major recipient of U.S. aid.

Mr. Putin’s direction bodes ill for Russia and for Russians. The country desperately needs modernization, both political and economic, but Mr. Putin is going backward. There will probably be more bloody noses before he is finished.