Most U.S. intelligence analysts, like most American observers, have often referred to the process unfolding in the Middle East as the “Arab Spring,” with its implicit message of democratic rebirth and freedom.

But some senior analysts are said to have argued for a more neutral term, such as “Arab Transition” — which conveys the essential truth that nobody can predict just where this upheaval is heading.

The uncertain transition rumbled on last week in Syria: President Bashar al-Assad’s hold on power appeared to weaken, with his military stretched to the breaking point in an attempt to control the protests. President Obama, evidently sensing that the endgame is near, Thursday called on Assad to step down.

Syria illustrates the paradox of the Arab transition. The courage of the Syrian people in defying Assad’s tanks is breathtaking. Yet this is a movement without clear leadership or an agenda beyond toppling Assad.

It could bend toward the hard-line Sunni fundamentalists who have led the street-fighting in Daraa and Homs, or to the sophisticated pro-democracy activists of Damascus. The truth is, nobody can predict the face of a post-Assad Syria.

The Syrian confrontation is already devolving into a regional proxy war. Iran has been rushing assistance to Assad, who is Tehran’s key Arab ally and provides a lifeline to the Hezbollah militia in Lebanon. To counter the Iranians, a newly emboldened Saudi Arabia has been pumping money to Sunni fighters in Syria. Damascus is the fault line — for Sunni-Shiite tensions, and for the confrontation between Iran and the U.S. and Israel.

Despite these uncertainties, Obama is right to demand that Assad must go. Some commentators have chided the White House’s hyper-caution. (Saudi Arabia, hardly a beacon of change, denounced Assad a week ago.) But I think Obama has been wise to move carefully — and avoid the facile embrace of a rebel movement whose trajectory is unknown.

America’s goal should be an inclusive democracy that enfranchises the Sunni fighters in the streets, yes, but also protects Alawites, Christians and Druze who fear a bloodbath.

As the Arab transition moves through summer toward fall, it’s a good time to take stock — and to remind ourselves that there won’t be any automatic movement toward prosperity and rule of law. The citizen revolt that began in Tunisia is surely a positive trend — and it’s unstoppable, in any event. But analysts offer some important cautionary points:

• The Arab movements for change will probably retard the process of economic reform that was under way in nations such as Egypt. President Hosni Mubarak was an arrogant leader, but over the last decade he did encourage free-market policies that helped boost Egypt’s growth rate over 5 percent.

Two architects of those pro-market policies were Prime Minister Ahmed Nazif and Trade Minister Rachid Mohamed Rachid. Both have now been charged with corruption. The populist anger is understandable but it won’t help Egypt get much-needed international investment.

• Democracy is likely to disappoint the protesters. They went into the streets to demand a better life — jobs, freedom from secret police, personal dignity — and they want these rights now. Hopefully, citizens in Egypt, Tunisia, Syria, Yemen and the rest will soon be able to vote for democratic governments.

But struggling democracies often aren’t very good at meeting the basic demands that spawned the revolutions. Asia put economic reform first, with political reform gradually following. The Arabs have decided to go the other direction — with uncertain consequences.

• The Arab transition needs to embrace the tolerance of secular societies rather than the intolerance of theocracy. That’s one lesson this generation could learn from the “Arab Renaissance” movements of the last century.

The Baath Party and the Nasserites are rightly rejected now, but in celebrating “Arab nationalism” they gave an identity to citizens that was broader than religion, sect or tribe. That spirit of inclusive identity will be essential for a happy Arab future.

Viewing events in the Arab world, President Obama has talked often of being “on the right side of history.” But frankly, that’s an incoherent concept.

History doesn’t have a side; it isn’t a straight line that moves inexorably toward progress. Movements that start off calling for liberation often produce the opposite.

What should guide U.S. policy in this time of transition is to be on the right side of America’s own interests and values.

Sometimes those two will conflict, requiring difficult choices, but they coincide powerfully in the departure of Syrian President Assad.

David Ignatius writes about foreign affairs for The Washington Post. He can be contacted at:

davidignatius@washpost.com