Washington has determined that the destruction of Iraqi leader Saddam Hussein's regime is of fundamental interest. The consequences of that war are one of the pressing issues. There is a very real possibility, verging on probability, that the outcome of a U.S. attack will be either the complete fragmentation of Iraq or the establishment of a regime incapable of maintaining its territorial integrity. This poses a core issue for the United States: how to manage the relative growth in power of Iran. The United States has tried to forge a relationship with Tehran, but that process has been tentative and not fully satisfactory. Iran is in no way under U.S. control.

Under the new geopolitics, the behavior of Iran is of greater significance to the United States than the behavior of almost any other country in the world. No agreement can guarantee Iran's behavior -- only a balance of power can. If Iraq no longer can carry out that function, there either will be no balance of power or the United States must find another player that is prepared to take on the role.

That is why Turkey's announcement last week that it intends to occupy northern Iraq in the event of a war is of such significance. The Turkish government announced that its forces would move up to 60 miles (95 km) into Iraq to prevent an influx of refugees. The true intent, of course, has less to do with refugees than with preventing the Kurds in Iraq from setting up an independent state.