Obama's 50-50 Russia Strategy.(International Edition; POINT OF VIEW)

Byline: Andrew Nagorski

Even to some of the closest observers of Russian foreign policy, it's almost impossible to know which direction Moscow is headed. One day it's threatening to station missiles aimed at Poland in its western enclave of Kaliningrad; the next, it's proclaiming its eagerness to take up Washington's offer to press the "reset button" on U.S.-Russia relations. One day, it's vowing to help with supply routes for NATO forces in Afghanistan; the next, it's offering Kyrgyzstan some $2 billion in loans and aid, emboldening the Central Asian country to demand the closure of the U.S. air base there. One day, it's signaling its solidarity with Western efforts to stop Iran from building nuclear weapons; the next, it's refusing to rule out the sale of sophisticated S-300 ground-to-air missiles to Tehran.

All this raises a key question: at President Barack Obama's meeting with Russian President Dmitry Medvedev in London on April 1, which Russia will he be seeing? Most likely, both leaders will accentuate the positive, voicing hopes for a new cooperative relationship between their two countries--and for good reason: Moscow and Washington have more in common than one might think.

For starters, both sides are eager for new nuclear-arms-control agreements that would allow them to scale back their arsenals and prevent a new arms race that neither side can afford in the midst of the current economic crisis. And the history of U.S.-Russian relations shows that talks on doomsday weapons tend to set the tone on all issues. A breakthrough on arms control could spill over into other fronts, including Afghanistan and Iran.

Moscow is more worried than it lets on about the prospect of a nuclear-armed Iran, despite its major commercial and arms deals with Tehran. Like Washington, it is well aware of the potential wild card this could be. An Iran armed with nuclear weapons would have a huge psychological impact, raising the confidence of Muslims throughout the region--including in rebellious regions of southern Russia and the ex-Soviet republics over the border.

The same factor--resurgent Islam--makes the quest for stability in Afghanistan as important to Russia as it is to the United States. Washington worries that Muslim extremists could spark more terrorist attacks on Western targets; Russia is concerned that Afghanistan's failure would spill over into Tajikistan and other border states, where Muslim extremists would destabilize pro-Russian governments.

In one sense, Afghanistan is a live threat to Russia. Victor Ivanov, the head of Russia's anti-narcotics service, recently ...