Moreover, transitions to democracy in the Middle East will be more perilous than those elsewhere because of factors unique to the region: the power of political Islam and the entrenched nature of sectarian and tribal loyalties.

Islam and democracy are by no means incompatible. However, religion and politics are intimately interwoven throughout the Middle East. Islamic tradition makes no distinction between mosque and state, helping Islamists win elections throughout the region. One result is a debilitating struggle between empowered Islamists and fractured secularists that is playing out in Egypt, Turkey, Tunisia and just about everywhere else.

Absent the Western tradition of separating the sacred from the secular — which came about only after the bloody wars of the Protestant Reformation — pitched battles over the role of Islam in politics will bedevil aspiring Middle East democracies for generations to come.

So, too, will sectarian and tribal politics make successful democratic transitions in the Middle East especially elusive. A sense of national belonging is the twin sister of democracy; nationalism is the social glue that makes consensual politics work. Egypt, like Turkey and Iran, is fortunate to have a strong national identity dating back centuries. But Egypt is nonetheless stumbling as it tries to put down robust democratic roots.

Social cohesion will be even harder to come by in many of the region’s other states — like Iraq, Syria and Lebanon — which are contrived nations cobbled together by departing colonial powers. They risk being split asunder by sectarian, ethnic and tribal cleavages.

Finally, Washington’s determined promotion of democracy compromises its credibility because doing so is often at odds with its own policies. Its closest allies in the Arab world, the Persian Gulf sheikdoms, are the region’s least democratic states. When Hamas won the Palestinian elections in 2006, America promptly sought to undermine the new government.

These departures from democratic principles are, as they should be, guided by concrete national interests. But as the Arab awakening unfolds, Washington’s leverage will further diminish unless its rhetoric catches up with its actions.

The United States should do what it can to shepherd the arrival of liberal democracy in Egypt and other parts of the Middle East. But the best way to do that is to go slow and help the region’s states build functioning and responsible governments. Democracy can wait.