These are challenging times for American foreign policy. Violent government crackdowns against pro-democracy protesters in the Middle East, new saber rattling in Tehran, and a fragile European Union under the weight of a widespread debt crisis underscore the difficulties facing U.S. policymakers and their allies. Here is a sampling of perspectives from several Harvard Kennedy School faculty members who are studying these developments and giving thought to how U.S. influence could affect the outcomes:“It is a new day in the Middle East and a time of real testing for American policy. Our vast military strength will do us little good in this revolutionary Arab moment. We must rely on our diplomatic dexterity to maintain American influence and purpose in this vital region. Some critics call for a more aggressive US role, even as the head of an armed intervention force in Syria. But it is not smart to try to lead the parade, as we almost always did in the past. Instead of rushing forward into the fray, the administration is right to proceed carefully, patiently, and at the side of our Arab friends and Turkey as we seek to preserve American interests in this greatest test yet of President Obama’s Middle East diplomacy,” writes Professor Nicholas Burns in The Boston Globe.