Marc Lynch lists several diplomatic moments that Obama "failed to capitalize on."
Take the exemplary June speech in Cairo, where Obama delivered a brilliant speech which captivated international and Muslim attention. It offered a real opportunity to reset American relations with the Islamic world, and to begin a new kind of relationship and engagement. But after the speech... almost nothing followed. Few new programs, few new initiatives, few efforts to capitalize on that moment. (And don't tell me about the number of text messages or twitter tweets sent during the speech -- could there be a more pointless metric for success?) I'm told that a number of new programs are in the works, but it's far too late -- they should have been "shovel-ready" on June 5. Now, the Cairo speech might as well have happened in the Jurassic period and the momentum of that one-time-only speech has been squandered.
Sometimes the lower profile is intentional, and correct. The administration was absolutely right to not take the lead during the Iranian electoral protests, helping to prevent the regime from making the U.S. the issue. It has also done a great job of quietly de-emphasizing al-Qaeda, rarely referring to it (except in the AfPak zone) and deflating rather than exaggerating its threat. But in so many other areas, better public diplomacy and strategic communications could make a real difference in shaping the conditions for foreign policy success.