WASHINGTON — In its decade-long slog to secure Afghanistan, the United States has juggled contradictory foreign policies in Uzbekistan and Kyrgyzstan, the fragile Central Asian states with key supporting roles in the war. There's the policy of engaging the two post-Soviet states for their own sake, promoting good governance, human rights, and business ties — the usual grab bag of U.S. diplomacy. Then there's the policy of using them as logistical hubs in the Afghanistan war.