In the wake of growing tension around Iran's nuclear program, 2012 looks like it will be another challenging year for both the United States and Russia. Perhaps the most difficult and time-consuming question confronting Washington and Moscow today is how best to proceed on Iran.

Even though Tehran has consistently denied allegations that it is seeking to develop a bomb, the latest International Atomic Energy Agency report appears to confirm what most analysts have long suspected. After presenting new evidence suggesting that Iran is secretly working on a nuclear weapon, nonproliferation experts have begun to think strategically of imminent dangers from Iran's nuclear ambitions.

Moscow and Washington have a shared interest in preventing Iran from acquiring nuclear weapons but they have divergent views on Iran. Washington sees Iran's nuclear activities as a pressing threat that must be eliminated; whereas Moscow has repeatedly stressed Iran's geopolitical and economic role as Russia's strategic partner in the sectors of petroleum, atomic energy and arms.

Given historical instability in the greater Middle East, the prospects of a nuclear Iran look disturbing. Paradoxically, Iran's possession of a nuclear weapon would change the strategic balance in the entire region and could fundamentally challenge Russia's security policy in the southern tier of the post-Soviet territory. A nuclear-ready Iran could embolden regional extremists and terrorist networks and eventually destabilize many countries in Eurasia. Such a scenario contains some serious risks for the Kremlin's security policy in Russia's southern borders and would have a number of potentially important strategic consequences for the south Caucasus and Caspian Basin.

Whether the United States and Russia will succeed in coordinating their policies on Iran will depend considerably on their ability to solve the complexities of the Iranian nuclear crisis. But there are already two important points of agreement between Washington and Moscow on the Iranian issue. Both are against nuclear weapons proliferation and both desire to defeat global terrorist networks that would like to get their hands on nuclear weapons.