There are many recurring debates in American foreign policy - for example, isolationism versus internationalism, and unilateralism versus multilateralism. But no debate is more persistent than that between those who believe that American foreign policy's principal purpose should be to influence the external behaviour of other states and those who hold that it should be to shape their internal nature.
This debate between "realists" and "idealists" is intense and long-standing. During the Cold War, there were those who argued that the United States should try to "roll back" the Soviet Union, bring down the communist system, and replace it with democratic capitalism.
Others deemed this to be too dangerous in an era defined by nuclear weapons, and the US opted instead for a policy of containment, working to limit the reach of Soviet power and influence.
As it turned out, after 40 years of containment, the Soviet Union and its empire unravelled, though this outcome was a by-product of US policy, not its principal purpose.
George W Bush was the most recent "idealist" proponent of making democracy promotion the main priority for US foreign policy. Bush embraced the so-called "democratic peace" theory, which holds that democracies not only treat their own citizens better, but also act better toward their neighbours and others.
It was, of course, his father, George HW Bush, who was a strong representative of the alternative, "realist" approach to American foreign policy.
Much of this debate can be viewed through the lens of American involvement with Iraq. George W Bush went to war with Iraq in 2003 to change the government. He expected regime change in Baghdad to lead to a democratic Iraq, a development that would in turn transform the region when people elsewhere in the Arab world saw this example and forced their own governments to follow suit.
By contrast, in the earlier Iraq war, the first President Bush, after amassing an unprecedented international coalition that succeeded in liberating Kuwait, did not press ahead to Baghdad to oust Saddam Hussein and his government, despite the urging of many that he do just that.
Nor did he intervene on behalf of the Shia and Kurdish uprisings that erupted just after the war ended early in 1991. To him, intervention would have placed US soldiers in the midst of a complex domestic struggle, one that would have cost enormous resources to sort out if it could be sorted out at all.
President Barack Obama appears to agree with this realist approach. The new US policy toward Afghanistan makes no mention of trying to transform that country into a democracy. On the contrary, as Secretary of Defence Robert Gates stated before Congress in January, "If we set ourselves the objective of creating some sort of Central Asian Valhalla over there, we will lose."
For his part, Obama said in March that "We have a clear and focused goal: to disrupt, dismantle, and defeat Al Qaeda in Pakistan and Afghanistan, and to prevent their return to either country in the future."
This shift is also evident in US policy toward China. Speaking during her trip to Asia in February, Secretary of State Hillary Clinton made clear that human rights issues would be a secondary concern in US-China relations.
Similarly, the joint statement issued by Obama and Russian President Dmitry Medvedev after their April 1 meeting in London, while mentioning that US-Russia relations would be "guided by the rule of law, respect for fundamental freedoms and human rights, and tolerance for different views", placed far greater emphasis on reducing nuclear arms, addressing Iran's nuclear programme, and stabilising Afghanistan. US support for Russia's admission to the World Trade Organisation was unconditional.
This change in US foreign policy is both desirable and necessary. Mature democracies do tend to act more responsibly, but immature democracies can easily succumb to populism and nationalism. It is difficult and time-consuming to build mature democracies. While encouraging the rule of law and the growth of civil society, the US still needs to work with other governments, democratic and otherwise. Pressing problems, such as the economic crisis, nuclear proliferation, and climate change, will not wait.
The good news is that history shows that it is possible to make peace with and work with non-democracies. Israel, for example, has had peaceful relations with non-democratic Egypt and Jordan for more than three decades. The US and the Soviet Union cooperated in limited ways (for example, in controlling nuclear arms) despite fundamental differences. Today, the US and authoritarian China have mutually beneficial trade and financial ties, and have shown on occasion that they can work together on strategic issues, for example in shaping North Korea's behaviour.
This is not to say that promoting democracy will have no role in American foreign policy. It will, and it should. But democracy promotion is too uncertain a proposition, and the world too dangerous a place, for it to occupy centre stage in what the United States does. Barack Obama's foreign policy will thus resemble that of George Bush - the father, that is, not the son.
Richard Haass, President of the Council on Foreign Relations, is the author of War of Necessity, War of Choice: A Memoir of Two Iraq Wars
This article appears in full on CFR.org by permission of its original publisher. It was originally available here.