Vice President Joseph Biden told a European security conference earlier this month that it was“time to press the reset button”and revisit the many areas where the United States and Russia can work together. The next day, Russia’s almost never conciliatory deputy prime minister, Sergei Ivanov, embraced the overture.

We are relieved that Washington and Moscow are talking about cooperation. There is certainly a lot in the relationship that needs resetting, starting with reviving negotiations to do away with thousands of nuclear weapons. But pressing the reset button cannot mean absolving Vladimir Putin’s Kremlin of its authoritarian ways.

President George W.Bush spent years looking the other way while Mr. Putin harassed opponents, stifled a free press and bullied Russia’s neighbors. While he was busy looking into Mr.Putin’s eyes, Mr.Bush also ignored Russia’s list of grievances - many illegitimate, but not all.

President Obama must not repeat either mistake. The Russians have given him fair warning of how difficult this relationship could be. Just days before Mr. Biden spoke, the Kremlin “encouraged” the former Soviet republic of Kyrgyzstan - with a $2.15 billion pledge of loans and aid - to give notice that it is closing an American base that supplies United States forces in Afghanistan.

Arms control may be the most promising area for early progress. The 2002 Moscow treaty, Mr.Bush’s one and only agreement, allows each country to deploy between 1,700 and 2,200 long-range nuclear weapons. They could easily go to 1,000 weapons each. A swift agreement also would send an important signal to North Korea, Iran and other potential nuclear scofflaws.

The administration also has begun hinting that it may be open to some compromise on Mr.Bush’s missile defense system planned for Poland and the Czech Republic. We are skeptical that the technology is anywhere near ready. We are also skeptical about the Russians’ insistence that the system poses any threat to their security. A healthy dialogue on the subject is in order. The Kremlin has offered to assist NATO with Afghanistan, President Obama’s top security challenge. Moscow has no love for the Taliban. And that is certainly worth testing. But if Washington has learned any lesson, it is that it must have multiple options for wartime supply routes - and Russia cannot have a chokehold. The administration also will have to test whether Moscow will do more to help end Iran’s nuclear program. That, too, is in Russia’s clear strategic interest, even though the Kremlin has yet to see it.

So far Mr.Obama has been quiet about Russia’s latest efforts to bully its neighbors. He will have to find his voice. After its war with Georgia last year, Russia defied international law by recognizing the independence of Abkhazia and South Ossetia. It recently went further and announced plans to establish bases there . While the Georgia dispute may not lend itself to quick solution, Moscow must not be allowed to think the world has acquiesced to its indefinite presence in Abkhazia and South Ossetia.

We’re not sure how Mr.Obama is going to find the right balance between cooperating with the Kremlin and avoiding enabling its bullying ways. But that can be the only basis for a sound relationship.