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Soft balancing can also impose real military costs on the United States. The United States may be a sole superpower, but it is geographically isolated. To project power in Europe, Asia, and the Middle East, the United States depends greatly on basing rights granted by local allies. The reality is that all of America's victories over the last decade-Iraq, Bosnia, Kosovo, and Afghanistan-depended on the use of short-legged tactical air power and ground power based in the territory of American allies in the region.

Without regional allies, the United States might still be able to act unilaterally, but would have to pay higher costs in blood and treasure to do so. Turkey's refusal to allow US ground forces on its soil has complicated American military planning; it increases the odds that what many thought would surely be a quick and decisive victory could become a more protracted ordeal.