In the past week, Syrian opposition groups have issued two contrasting appeals to the international community. On Saturday 28 July, the Syrian National Council demanded new and better weaponry for the insurgents battling the Bashar al-Assad regime. "We want weapons that would stop tanks and jet fighters," SNC chief Abdul-Basset Sieda told a news conference in Abu Dhabi. Two days earlier, at the Community of Sant'Egidio in Rome, representatives of 10 opposition organisations asked the world to assist Syria in another way: forcing both sides to reach a peaceful resolution of the conflict. Their joint statement concluded: "We cannot accept Syria being transformed into a theatre of regional and international conflict. We believe the international community has the strength and the necessary ability to find a consensus that would be the basis of a political solution to the current dramatic crisis, based on the imposition of a ceasefire, the withdrawal of the military, the release of detainees and the kidnapped, the return of refugees, emergency assistance for the victims, a real global negotiation that excludes no one and a process that would be completed with real national reconciliation based on justice".

The choice confronting the world is not between the Assad regime and the opposition, but between two oppositions. One seeks international military intervention to enable it to overthrow the regime. The other strives for change through civil disobedience and dialogue and rejects military interference by foreign powers whose hostility to Syria pre-dates their recent discovery of the country's woes.

This conflict was born as a peaceful rebellion evolving into a popular revolution. Violent suppression of unarmed demonstrators led some opponents to take up arms in defence of the right to protest and demand change. The armed men were a minority among dissidents who recoiled from the despoliation of their country that would inevitably accompany a violent uprising, yet they gained the ascendancy by the force of their actions and the international support they gained for their choice of the rifle over the banner.

As casualties mounted, advocates of a military solution dominated both the regime and the opposition camps. The centre, inevitably, could not hold. Battles that had been limited to border zones, where rebels were easily supplied from Turkey, Jordan and Lebanon, spread to the rest of the country. Damascus and Aleppo, whose populations had for the most part either supported the regime or opposed it without resort to weapons, have become in the past three weeks theatres of bloody confrontation.

The rebels, advised by intelligence officers from western countries working in Turkey and Lebanon, took outlying neighbourhoods of Damascus. The regime, inevitably, used all the means at its disposal to drive them out and retake those areas. The next target of the rebels' strategy was Aleppo, where the pattern is repeating itself: the rebels established themselves in the suburbs, residents fled and the regime returns with infantry, armour and air power to "restore" order. In the meantime, the United Nations estimates that 150,000 Syrians have fled the country and as many as 20,000 have died – on both sides, to be sure, but most casualties are those in the middle who are cursing both houses.

How did Syria reach this point, and where is it going? Neither side can lay claim to the legitimacy of election by popular mandate. No one voted in a fair election for either Bashar al-Assad, who inherited his father's mantle as if Syria were a monarchy, or the Free Syrian Army militias with the Syrian National Council.

There are wars, and there are civil wars. Before the Red Cross withdrew from Syria last week, it declared this was a civil war. This means it is no longer a rebellion, but a battle for power between contending factions. Neither the Free Syrian Army nor the government recognises the other. Both refuse to speak to each other. Their external benefactors (for the regime, Russia, Iran and Iraq; for the opposition, Turkey, Saudi Arabia, Qatar, the US, France and Britain) are encouraging their intransigence.

For outsiders, whose own countries will not be the chessboard on which this game is played, war makes more political capital than the more subtle and difficult route of negotiation and compromise. Yet which is more likely to preserve Syria, its secularism, its economy and the healthy relations among its communities – civil war, as in Spain, Lebanon and Yugoslavia or the example of Nelson Mandela meeting the enforcers of apartheid? When the British government and the Irish Republican Army swallowed pride and distaste to negotiate seriously, rather than win outright, the war in Northern Ireland ended.

The rebels receive foreign support, funds and weapons, as the regime says. And, as the opposition says, the regime has blood on its hands. Yet to whom will they speak if not to each other? Both claim to be Syrians fighting for Syria. Call their bluff. Let Russia bring Assad kicking and screaming to the table, while the US and its allies do the same with the opposition. Is that course really less realistic, or less helpful to Syria, than all-out war?

Listen, for a moment at least, to the people who signed the Rome statement. They include the Democratic Forum's Michel Kilo, a respected writer from northern Syria who did his first prison stretch under Assad's father 30 years ago. When he returned after years in exile, he landed back in prison. Yet he clings to the nonviolence that he believes will save Aleppo and other cities from destruction. Another is Riad Draar of the Islamic Democratic Current. Five years in a Syrian prison for "inciting sectarian strife" and "spreading false news" did not turn him to violence. They and the other signatories have credibility among Syrians aware of the both the regime's and the insurgents' flaws. One sentence in the Rome statement resonates with Syrians who have been expelled from their homes or seen those they love killed by either side: "The military solution is holding the Syrian people hostage and does not offer a political solution capable of responding to the people's deepest aspirations."