As the military expert Anthony Cordesman, who has advised the U.S. Army in Afghanistan, explained in The Washington Post recently, it requires “a significant number” of U.S. reinforcements and time to do what the Kabul government has failed to do, because it remains “a grossly overcentralized government that is corrupt, is often a tool of power brokers and narco-traffickers, and lacks basic capacity in virtually every ministry.”
Source: wiktionary