The partial ceasefire in Syria announced by the United States and Russia on February 23 has been met with less than overwhelming optimism, and, after so much bloodshed and the entrenchment of hardline positions, it is not hard to see why. The accord stipulates that the Syrian government and allied groups, including Russia, end attacks against opposition forces that are party to the agreement and these opposition forces suspend military operations. Both sides must refrain from seizing additional territory and allow “rapid, unhindered and sustained access” to humanitarian agencies.

Even incomplete implementation would be good news for the Syrian people, more than half of whom have been forcibly displaced, with nearly half of those fleeing into exile. More than 13 million people, half of them children, depend on humanitarian aid for survival. At least a quarter million Syrians have died, most of them noncombatants.

But there is no guarantee that the parties will honor the ceasefire. Not only that, but the largest rebel groups, including ISIS and the rival Al Qaeda–aligned Al Nusra Front, did not even participate in the negotiations. They have vowed to continue fighting.

The greatest hope for a peaceful and democratic Syria is its civil society, now in tatters as a result of regime repression and the rise of the militias.

Another obstacle to successful implementation is that the United States and Russia, which chair the international task force charged with implementing the ceasefire, have little leverage over their allies.  During the Cold War, the superpower rivals wielded far more influence over their respective proxies. But the Syrian regime is stronger and more autonomous than many of those former proxies. Meanwhile, the opposition is divided into scores of armed militia with their own agendas, and the regional backers of the regime and its opponents—such as Iran, Turkey, and the Arab monarchies—are arguably more influential than Russia and the United States. More fundamentally, while the internationalization of the civil war has tragically intensified and prolonged the suffering, the conflict remains primarily a Syrian one.

Despite this, seventeen other nations—European and Middle Eastern, as well as the United States and China—were involved in the difficult diplomatic efforts. None of them ultimately benefits from the conflict, which has spawned such a vast humanitarian crisis and created such instability in the region that—not withstanding their competing geopolitical interests—all have motivation for ending the war.

The ceasefire—or “cessation of hostilities,” as negotiators call it—represents a considerable reduction in American ambitions. Recognizing that the brutal repression and innumerable war crimes inflicted by the corrupt and autocratic regime of Bashar Assad lie at the root of the conflict, the United States, allied governments, and the rebels had long insisted on Assad’s removal from power as a condition of any settlement. But now, belatedly, these allies understand that Assad’s ouster is not a realistic outcome in the foreseeable future. Thus they have come to accept a ceasefire as the best alternative for the time being.

Even if the agreement reduces violence and enables a political process, it will be hard to depose Assad. Unlike most dictatorships overthrown by either armed or unarmed struggle in recent decades, the power in Damascus does not rest in the hands of a single individual. Tunisia’s Zine El Abidine Ben Ali, Egypt’s Hosni Mubarak, Libya’s Muammar Gaddafi, and Yemen’s Ali Abdulah Saleh led personalist dictatorships. The ruler and a small circle of family and officials dominated populations by means almost entirely of fear and patronage. By contrast, and despite all his violence and corruption, Assad enjoys genuine loyalty—he still has a social base. A fairly large minority of Syrians—consisting of Alawites, Christians and members of other minority communities, Baath Party loyalists and government employees, the professional armed forces and security services, and the largely Sunni crony capitalist class nurtured by the regime—cling to Assad’s government. Collectively, these supporters are sufficiently numerous and powerful to prevent anti-regime victory, assuming they stick together. And a cascade of defections is unlikely given that the alternative to Assad is perceived to be rule by totalitarian Salafist movements such as ISIS and Al Nusra Front.

It is not only regime loyalists who might, at this point, prefer to keep in Assad in power, in light of the possible replacements. During the first six months of the uprising in 2011, when the anti-regime movement was largely nonviolent, pro-democratic, and supported by a more diverse coalition, it appeared the regime could eventually be supplanted with a more liberal government. However, since turning to armed struggle and witnessing the resulting rise of Islamist extremists to the forefront of the opposition, many Syrians who once sought to topple the regime now see it as the lesser evil.

Thus regime opponents, too, have tempered their exepectations. With outright military victory by any side unachievable, the government and most of the more moderate rebel groups see the ceasefire agreement as the best attainable option.

The United States hopes that the ceasefire agreement will force some of the more moderate Islamist armed groups—a number of which have been supported by Turkey and some Arab Gulf States and have been willing until now to cooperate with Al Nusra—to split from the radicals. This marks a shift in U.S. strategy. Despite concern about Al Nusra’s radicalism, the United States and its allies had initially hoped the organization’s growing military prowess would force the Assad regime to back a coalition government led by moderate oppositionists. However, the Russian and Iranian intervention, which has forced Al Nusra and its allies to retreat from areas previously under their control, has compelled Washington to recalculate.

Further complicating the situation for Western powers is the “commingling,” acknowledged by State Department spokesperson Mark Toner, between more moderate Western-backed rebel groups and Al Nusra forces, due to the latter’s superior military organization and capabilities. Since Al Nusra is not party to the ceasefire and will still be subjected to Syrian and Russian air strikes, Washington has made clear to these moderate groups that they the need to separate themselves operationally and geographically from Al Nusra to avoid being attacked. While more moderate Islamist groups such as Jaish al Islam and the secular militias will make the effort to separate themselves, Ahrar al Sham—the strongest armed opposition group after ISIS and Al Nusra—is too closely integrated politically and militarily with Al Nusra to do so. It will remain in the fight.

In short, even if all of the ceasefire signatories uphold the agreement, the fact that it excludes the three most powerful armed opposition groups means that much of the violence will continue.

This is intentional. A primary goal of both the domestic and international players implementing the ceasefire is to enable combatants to focus on weakening ISIS, which has emerged as the most powerful of the Damascus regime’s armed opponents, controlling as much as one-third of the country. Yet, while it has taken advantage of the chaos in Syria to expand its areas of territorial control, ISIS is primarily an Iraqi-led organization, a direct outgrowth of the 2003 U.S. invasion and the sectarian divisions spawned by the subsequent occupation and counterinsurgency war. Regardless of what happens in Syria, ISIS will retain control of large sections of northwestern Iraq, continue attempts to expand its foothold in Libya and elsewhere, and inspire terrorist attacks globally.

And even if the partial ceasefire holds, the humanitarian crisis is eased, and radical Islamists are pushed back, an overall negotiated settlement remains a long way off. A corrupt autocratic regime will remain in power in Damascus and other areas, while the rest of the country is ruled by a patchwork of fractious armed groups. The many sides appear unwilling to compromise or even to recognize each other’s legitimacy. A society that until recently was a largely secularized mosaic of religious and ethnic communities has been shattered by violent sectarian and ideological divisions and is unlikely to heal soon.

One of the great ironies of the conflict is that the initially unarmed civil insurrection that challenged the Assad regime in 2011 was among the most impressive pro-democracy uprisings in history in terms of its broad base of support, creative uses of strategic nonviolent action, and tenacity in the face of brutal repression. It was nearly a year before this popular resistance struggle was supplanted by armed groups.

It is this early approach to revolution that must be cultivated anew. The greatest hope for a peaceful and democratic Syria is its civil society, now in tatters as a result of regime repression and the rise of the militias. Yet that beleaguered civil society represents the majority of Syrians; these are the people who deserve international support. The future of the country is too important to be left to the people with guns.

The best thing outside powers can do in the interest of peace is to include civil society groups in future negotiations, listen to what they have to say, and refrain from imposing top-down solutions that ignore the Syrian people. For a peace settlement lacking a popular mandate cannot be sustained.