Afghanistan is very different. The Pashtuns—whatever they themselves may say and think—are less than 50 percent of the population. As already stated, other ethnic groups have immensely strengthened their political and military power over the past four decades of war. The Afghan state tradition has always been weak, and outside limited elites have never managed to generate a strong common sense of state nationalism.

After the fall of the Communist state in 1992, Afghanistan descended into horrendous ethnic warfare, in which the city of Kabul was destroyed and the country was divided up into warlord fiefdoms. It was because they promised to end this catastrophe that the Taliban—representing rural Pashtun conservatism but also Pashtun traditions of state-building—gained so much support. They were bitterly resisted by forces representing the non-Pashtun nationalities, and even though these had little outside support (except from Iran), the Taliban never managed to conquer the whole of Afghanistan.

RATHER THAN a clear-cut Taliban victory, the collapse of the existing Afghan state and the fall of Kabul to the Taliban would almost certainly lead to a civil war. This would pose real dangers. The greatest threat to America’s global position and the ideological basis of U.S. soft power in the world does not come from the rise of China or even the rise of right-wing populism in the United States itself. It comes from the impact of Muslim migration on Europe, and (reinforced by the socio-economic decline of the white working classes) the resulting swing of European populations to chauvinist positions hostile to the European Union and often sympathetic to Russia. In Germany, the wave of Syrian refugees has largely wrecked the Social Democratic Party and forced it into what looks like a permanent coalition with Angela Merkel’s Christian Democratic Union (CDU). The cdu, and the coalition, are now in danger as the CDU’s more right-wing sister party, the Bavarian Christian Social Union, moves to more and more anti-immigrant positions in a bid to save itself from being overtaken by the new and quite radical Alternative for Germany party.

Afghans already make up the second largest group of refugees to Europe after Syrians. A collapse of the Afghan state and intensified civil war would greatly increase their numbers, while adding to Europe’s moral dilemma—for on what legal or moral grounds, given the Western role of the past seventeen years in Afghanistan, could eu members refuse to grant asylum to refugees from the Taliban? To prevent masses of Afghan refugees heading to Europe would require not only a new deal with Turkey, but one with Iran as well—at which point the eu would find itself completely at odds with the United States.

In his latest book, The Retreat of Western Liberalism, Edward Luce of the Financial Times has written that European democracy will not survive another decade like the last one. He has a point. The greatest threat from Afghanistan to the West is not terrorism, Islamist revolution or regional instability, but its potential impact on the political systems of European countries three thousand miles away (of course, a U.S. citizen might well reply that in that case European countries should be doing the fighting in Afghanistan—but realistically speaking there is no point in even suggesting this).

This danger is an entirely sufficient reason for the United States to go on fighting in Afghanistan, at least as long as costs in U.S. blood and treasure remain at their present level and the Afghan state does not implode for its own internal reasons. This military strategy should in no way exclude peace overtures to the Taliban and serious, realistic American thinking about what a peace settlement would entail.

The most disagreeable result of such thinking for the U.S. establishment is not the prospect of the Taliban with a major share of power in Kabul. It is that any Afghan settlement can only be established and maintained if China plays the leading role—something that would most probably require a commitment eventually to withdraw U.S. bases from Afghanistan. This is because only Beijing now has the kind of influence over Islamabad that can bring the Taliban’s backers in the Pakistani army fully on board, and because Chinese (and Russian) influence is also necessary to gain full Iranian acquiescence. Chinese money will also be necessary to prop up the Afghan state if the United States makes a peace settlement the excuse to slash financial aid. Afghanistan may therefore become a test-case both for the relative decline of American power and for Washington’s willingness to respond to this decline by seeking cooperation with other great powers.

Nor, in the case of Afghanistan, should this be seen as a tragedy. After all, U.S. interest in Afghanistan was virtually nonexistent until the late 1940s and the start of the Cold War. The U.S. role remained extremely limited until the Soviet intervention of 1979. Nor did the subsequent U.S. involvement bring the United States anything good. Afghanistan may be a good opportunity for the United States to remember that it is not in fact a Central Asian power, and that there may be advantages to leaving messes for local powers to sort out.

Anatol Lieven is a professor at Georgetown University in Qatar and author of, among other books, Pakistan: A Hard Country.