Two years into the Arab Spring, euphoria seems a thing of the past. The heady days of protest and triumph have been replaced by outrage at the atrocities in Syria, frustration that the region's monarchs remain largely immune to pressure for reform, fear that the uprisings’ biggest winners are Islamists who might limit the rights of women, minorities, and dissidents, and disappointment that even in countries that have experienced a change of regime, fundamental change has been slow and unsteady. Difficult as it is to end abusive rule, the hardest part may well be the day after.

It should be no surprise that building a rights-respecting democracy on a legacy of repression is not easy. The transitions from communism in Eastern Europe and the former Soviet Union yielded many democracies, but also many dictatorships. Latin America's democratic evolution over the past two decades has been anything but linear. Progress in Asia and Africa has been uneven and sporadic. Even the European Union, which has successfully made democratic reform and respect for human rights conditions of membership, has had a harder time curbing authoritarian impulses once countries—most recently Hungary and Romania—became members.

Moreover, those who excelled at overthrowing the autocrat are often not best placed to build a governing majority. The art of protest does not necessarily match the skills needed for governing. And allies in ousting a despot are sometimes not the best partners for replacing despotism.

But those who pine for the familiar days of dictatorship should remember that the uncertainties of freedom are no reason to revert to the enforced predictability of authoritarian rule. The path ahead may be treacherous, but the unthinkable alternative is to consign entire peoples to a grim future of oppression.

Building a rights-respecting state may not be as exhilarating as toppling an abusive regime. It can be painstaking work to construct effective institutions of governance, establish independent courts, create professional police units, and train public officials to uphold human rights and the rule of law. But these tasks are essential if revolution is not to become a byway to repression by another name.