The heart of President Obama's message to a Middle East in ferment has been that Islamists need to join the political process. They are cajoled and encouraged by Washington to believe in elections and democracy.
That is why the Cairo military coup is so profoundly unwelcome at the White House.
How can America now persuade radical Islamists anywhere to engage in politics? What's the point when success like that enjoyed by the Muslim Brotherhood in Egypt is simply subverted by the military?
Now the extremists across the region can sneer at the Brotherhood's naive misjudgements and mock their decision to participate in the democratic process.
White House advisers are weary of confronting daunting Middle East crises in which there are no good policy options.
Egypt, Syria, Iran, Palestine, Iraq, even the protests in Turkey and Bahrain - all are events where America is largely a spectator, unable to exercise meaningful power.
After four decades of investing in Middle East peace-making, the frustration for the White House is considerable.
The world needs Egypt to be stable and peaceful. It needs Cairo to be a beacon of political and cultural vitality.
Now the trajectory of this pivotal country is likely to be a tragic and suffocating replay of the 1990s: the Muslim Brotherhood driven underground, Egypt's prisons becoming training camps for another generation of militants, Egyptian and Western interests targets of an Islamic insurgency.
Nobody will win from events this week in Cairo.
Except Bashar al-Assad. The Syrian President will see this as vindication for not surrendering power. Look, he will now argue, even Egypt couldn't let Islamists take over without buyer's remorse.
Assad will take encouragement from the belief that secular military dictatorships are not destined to die. As Egypt shows, they may be the future as well as the past.