KABUL, Afghanistan — In recent years, the growing resentment in Afghanistan toward American forces’ raids and airstrikes has been balanced, in part, by concerns about what might happen after foreign troops leave.

That ambivalence about the American presence here was again illustrated on Wednesday in reactions to President Obama’s announcement that the United States would leave 9,800 troops in Afghanistan after the NATO-led combat mission here ends this year, and that nearly all troops would be gone by the end of 2016.

In interviews with officials and business leaders, one common reaction to the decision was the belief that too few American troops were being left behind for too few years.

Some worried that announcing such a short deadline would allow the Taliban to easily wait out the American presence, or that the quick drawdown would put Afghanistan’s weak economy at greater risk of failure.