By George Friedman

In recent weeks, some of the international system's unfinished business has revealed itself. We have seen that Ukraine's fate is not yet settled, and with that, neither is Russia's relationship with the European Peninsula. In Iraq we learned that the withdrawal of U.S. forces and the creation of a new Iraqi political system did not answer the question of how the three parts of Iraq can live together. Geopolitical situations rarely resolve themselves neatly or permanently.

These events, in the end, pose a difficult question for the United States. For the past 13 years, the United States has been engaged in extensive, multidivisional warfare in two major theaters — and several minor ones — in the Islamic world. The United States is large and powerful enough to endure such extended conflicts, but given that neither conflict ended satisfactorily, the desire to raise the threshold for military involvement makes logical sense.

U.S. President Barack Obama's speech at the U.S. Military Academy at West Point sought to raise the bar for military action. However, it was not clear in the speech what Obama meant in practical terms when he said:

"Here's my bottom line: America must always lead on the world stage. If we don't, no one else will. The military that you have joined is and always will be the backbone of that leadership. But U.S. military action cannot be the only — or even primary — component of our leadership in every instance. Just because we have the best hammer does not mean that every problem is a nail."

Given events in Ukraine and Iraq, the president's definition of a "nail" in relation to the U.S. military "hammer" becomes important. Military operations that cannot succeed, or can succeed only with such exorbitant effort that they exhaust the combatant, are irrational. Therefore, the first measure of any current strategy in either Ukraine or Iraq is its sheer plausibility.

The Ongoing Ukraine Crisis

In Ukraine, a pro-Russian president was replaced by a pro-Western one. The Russians took formal control of Crimea, where they had always had overwhelming military power by treaty with Ukraine. Pro-Russian groups, apparently supported by Russians, still fight for control in Ukraine's two easternmost provinces. On the surface, the Russians have suffered a reversal in Ukraine. Whether this is truly a reversal will depend on whether the authorities in Kiev are able to rule Ukraine, which means not only forming a coherent government but also enforcing its will. The Russian strategy is to use energy, finance and overt and covert relationships to undermine the Ukrainian government and usurp its power.

It is in the interest of the United States that a pro-Western Ukraine emerges, but that interest is not overwhelming enough to warrant a U.S. military intervention. There is no alliance structure in place to support such an intervention, no military bases where forces have accumulated to carry this out, and no matter how weakened Russia is, the United States would be advancing into a vast country whose occupation and administration — even if possible — would be an overwhelming task. The Americans would be fighting far from home, but the Russians would be fighting in their backyard.

Ukraine is not a nail to be hammered. First, its fate is not of fundamental American interest. Second, it cannot be driven into the board. The United States must adopt an indirect strategy. What happens in Ukraine will happen. The place where the United States can act to influence events is in the countries bordering Ukraine — most notably Poland and Romania. They care far more about Ukraine's fate than the United States does and, having lost their sovereignty to Russia once in the last century, will be forced to resist Russia again. Providing them support with minimal exposure makes sense for the United States.

The Complexities of Iraq

Iraq consists of three major groups: Shia, Sunnis and Kurds. The United States left Iraq in the hands of the Shiite-dominated government, which failed to integrate the Kurds or the Sunnis. The Kurdish strategy was to create and maintain an autonomous region. The Sunnis' was to build strength in their region and wait for an opportune moment. That moment came when, after the recent election, Iraqi President Nouri al-Maliki failed to quickly form a new government and seemed intent on re-creating the failed government of the past.

The Sunnis did not so much invade as arise, taking control of Sunni areas and to some extent coordinating activities throughout the region. They did not attack the Kurdish region or predominantly Shiite areas. Indeed, the Shia began to mobilize to resist the Sunnis. What has happened is the failure of the central government and the assertion of regional power. There is no native power that can unite Iraq. No one has the strength. The assumption is that the United States could hold Iraq together — thus the demand by some in Iraq and the United States that the United States massively intervene would make sense.

As in Ukraine, it is not clear that the United States has an overriding interest in Iraq. The 2003 invasion was more than a decade ago, and whatever decisions were made then belong to historians. The Sunni uprising brings with it the risk of increased terrorism and obviously gives terrorists a base from which to conduct attacks against the United States. By that logic, the United States ought to intervene on behalf of the Kurds and Shia.

The problem is that the Shia are linked to the Iranians, and while the United States and Iran are currently wrapped up in increasingly complex but promising negotiations, the focus is on interests and not friendship. The 2003 invasion was predicated on the assumption that the Shia, liberated from Saddam Hussein, would welcome the United States and allow it to reshape Iraq as it desired. It was quickly discovered, however, that the Iraqi Shia, along with their Iranian allies, had very different plans. The U.S. invasion ultimately failed to create a coherent government in Iraq and helped create the current circumstance. As much as various factions would want the United States to intervene on their behalf, the end result would be a multi-sided civil war with the United States in the center, unable to suppress the war with military means because the primary issue is a political one.

That, of course, leaves the possibility of an increased threat of terrorism. There are 1.6 billion Muslims in the world, and some of them are prepared to engage in terrorist activity. It is extremely difficult, however, to figure out which are inclined to do so. It is also impossible to conquer 1.6 billion people so as to eliminate the threat of terrorism. Given the vast territory of the Islamic world, Iraq may be a convenience, but occupying it would not prevent Sunni or Shiite terrorism from arising elsewhere. Defeating an enemy army is much easier than occupying a country whose only mode of resistance is the terrorism that you intend to stop. Terrorism can be defended against to some extent — mitigated, observed perhaps — but in the end, whether the Sunni regions of Iraq are autonomous or under extremist rule does little to reduce the threat.

The Kurds, Sunnis and Shia are hostile to each other. Saddam controlled the country through the secular institutional apparatus of the Baath Party. Absent that, the three communities continue to be hostile to each other, just as the Sunni community in Syria is hostile to the Alawites. The United States is left with a single viable strategy: to accept what exists — a tripartite Iraq — and allow internal hostilities to focus the factions on each other rather than on the United States. In other words, allow an internal balance of power to emerge.

The Limited Use of the U.S. "Hammer"

When we consider Ukraine and Iraq, they are of course radically different, but they have a single thing in common: To the extent that the United States has any interest in the regions, it cannot act with direct force. Instead, it must act with indirect force by using the interests and hostilities of the parties on the ground to serve as the first line of containment. If the United States intervenes at all, it will do so by supporting factions that are of interest to Washington. In Ukraine, this would mean supporting the former Soviet satellite states in Central Europe. In Iraq, it would mean applying sufficient force to prevent the annihilation of any of the country's three major groups, but not enough force to attempt to resolve the conflict.

Americans like to have a moral foundation for their policy; in the cases of Ukraine and Iraq, the foundation is simply a necessity. It is not possible for the United States to use direct force to impose a solution on Ukraine or Iraq. This is not because war cannot be a solution to evil, as World War II was. It is because the cost, the time of preparation and the bloodshed of effective war can be staggering. At times it must be undertaken, but those times are rare. Constant warfare with insufficient forces to impose political solutions in countries where the United States has secondary interests is a prescription for the worst of both worlds: a war that ends in defeat.

Limiting wars to those that are in the national interest and can be won eliminates many wars. It substitutes a much more complex, but no less realist and active, approach to the world. Underwriting nations that find themselves in a position of having to act in a way that supports American interests is one step. Another is creating economic bonds with nations that will shape their behavior. There are other tools besides war.

The simultaneous fighting in Ukraine and Iraq proves two things. First, the United States cannot avoid global involvement because in the end, the globe will involve itself with the United States. Becoming involved earlier is cheaper. Second, global involvement and large-scale warfare are not the same thing. The situation in Ukraine will play itself out, as will the one in Iraq. It will give the United States enough time to determine whether and how much it cares about the outcome. It can then slowly begin asserting itself, minimizing risks and maximizing rewards.

This is not a new strategy for the United States, which has vacillated from pretending it is immune from the world to believing it can reshape it. Dwight Eisenhower was an example of a U.S. president who avoided both of those views and managed to avoid involvement in any major war, which many would have thought unlikely. He was far from a pacifist and far from passive. He acted when he needed to, using all means necessary. But as a general, he understood that while the threat of war was essential to credibility, there were many other tools that allowed Washington to avoid war and preserve the republic.

Eisenhower was a subtle and experienced man. It is one thing to want to avoid war; it is another to know how to do it. Eisenhower did not refuse to act, but instead acted decisively and with minimal risk. Obama's speech at West Point indicated hesitancy toward war. It will be interesting to see whether he has mastered the other tools he will need in dealing with Ukraine and Iraq. It helps to have been a warrior to know how to avoid war.

I once wrote that the United States, stunned in 1991 to discover it was the world's only superpower, emerged into a natural period of adolescence, swinging from a belief in its omnipotence to a sense of worthlessness. I argued that this was a necessary passing phase that ultimately forced the United States toward a coherent path. Today, it is not yet on that path, but it is beginning to find its way. Eisenhower should be borne in mind.