The second round of peace talks in Geneva between representatives of Bashar Al-Assad’s regime in Syria and rebel forces has ended with both sides blaming each other for the lack of progress. Beyond the finger-pointing, however, lies a growing danger to the goal of a negotiated settlement. The civil war’s religious divides are widening, making compromise unthinkable.

Representatives of the Syrian regime went to Geneva solely with the hope of convincing the opposition to let President Bashar al-Assad stay in power so he can forge an alliance against jihadist forces fighting in Syria, most notably the al Qaeda affiliates Jabhat al-Nusra and the Islamic State in Iraq and the Levant. Their argument — one that many, including former U.S. Ambassador to Iraq Ryan Crocker, have made — was that Assad is better than any likely alternative.

But the Syrian National Coalition, representing opposition forces, rejected the proposal outright. The coalition, which purports to be a post-Assad transitional government in waiting, has decided, along with Secretary of State John Kerry, that al Qaeda will be dealt with after Assad is gone. Its standing, however, is severely constrained by its lack of political credibility on the ground. It has become little more than a vehicle for Qatar and Saudi Arabia to vie for control of Syrian politics.

The problems in Syria, however, are far greater than the shortcomings of each side’s negotiating teams in Geneva. When the civil war began in 201l, it was a fight between Syrians demanding greater civil rights and a government that ultimately provoked them into violent confrontation through its own brutality. That political struggle quickly morphed into a wider sectarian war between Sunni and Shia, flaring up across the Middle East.

Shia Iran was an early — and vital — financial and military supporter of Assad. It is intent on make sure he does not fall. Hezbollah’s decision to send fighters into Syria last year, at Iran’s command, to strengthen Assad’s hand made the region’s Sunni giant, Saudi Arabia, even more fearful of creeping Shia hegemony.