Henry Kissinger writes:

The complexities of an exit strategy are compounded because relations with Pakistan and Iran are severely strained. These countries do not have the option of withdrawing from the neighborhood. If their interests in Afghanistan are not related to ours to some extent, Afghanistan will exist under permanent threat. Without a sustainable agreement defining Afghanistan’s regional security role, each major neighbor will support rival factions across ancient ethnic and sectarian lines — and be obliged to respond to inevitable crises under the pressure of events. That is a prescription for wider conflict. Afghanistan could then play the role of the Balkans prior to World War I.

Such an outcome would threaten the security of Afghanistan’s neighbors more than America’s. A partly regional, partly global diplomatic effort is needed to accompany direct negotiation with the Taliban. So long as America bears the primary burden, Afghanistan’s neighbors avoid difficult decisions. To the extent that U.S. postwar withdrawal is made explicit and inexorable, they will be obliged to take another look. The formal deadline established by NATO, the implicit Obama administration deadline and the public mood make it impossible to persist in an open-ended civil war. An immediate withdrawal largely for symbolic reasons would risk falling between all shoals. A multilateral diplomacy that defines a common international security interest proscribing terrorist training centers and terrorist infrastructure in Afghanistan should be undertaken urgently. To encourage this process, a deadline should be established for reaching a residual force — say, in 18 months to two years, with the major reductions coming at the end of the process. Should a reliable international enforcement mechanism emerge, the U.S. residual force can be merged into it. A regional conference is the only way a bilateral negotiation with the Taliban can be enforced. If the process proves in­trac­table, Afghanistan’s neighbors will eventually have to face the consequences of their abdication alone.

After America’s withdrawals from Iraq and Afghanistan and the constraint to our strategic reach produced by the revolution in Egypt, a new definition of American leadership and America’s national interest is inescapable. A sustainable regional settlement in Afghanistan would be a worthy start.