By Fareed Zakaria, CNN

Kofi Annan’s resignation as the U.N. and Arab League joint special envoy is a blow to any hopes that the situation in Syria could go down a stable path. It has also dashed hopes that an early route could be found to an inclusive government that could oversee decreasing levels of violence. Annan represented the possibility of something positive for Syria, and his departure is a sign that things are going to continue to spiral downwards.

There are two basic problems in Syria – an internal and an external political divide. The internal divide is evident every day. We have a brutal regime that is using maximum force, one that is making no concessions and that is simply holding onto power by any means possible. That is the principle problem in Syria, and one that can only be resolved if Bashar al-Assad and the people around him are deposed from power.

But there’s also a sectarian problem in Syria as is evidenced by the fact that minorities, who comprise 40 percent of the population, don’t seem to have joined the opposition. The Alawites, of course, who make up about 12 percent of Syria, are sticking with the Alawite-dominated regime. But the Christians appear to be doing so as well, for fear of what would happen to them in a majoritarian and more Islamist Syria. Other Syrian minorities such as the Kurds also don’t seem part of the Free Syria Army.

Right now, the battle is between an Alawite regime and a Sunni opposition. If this conflict really does become increasingly sectarian in nature, then we really may have even greater problems ahead. Think of the example of Iraq, where a Sunni-dominated regime was toppled, but then unleashed sectarian conflict.

What Syria needs is an end to the Assad regime but then some kind of political deal between the old and new guard. The core elements of the regime would have to step down or be ousted. But the opposition would also need to accept a post-al-Assad scenario in which some elements of the old system are kept in place, if only so that those elements don’t fight until the bitter end.

The second divide is the external divide, between the West on one side and China, Russia and Iran on the other. The Chinese, Russians and most importantly the Iranians are supporting the regime for different reasons. For the Iranians, Syria is their strongest ally and proxy in the region. Tehran is all in – it has bet on this regime, which is a source of regional influence, and so it has tried to prop it up. There’s a sectarian element to this – the Iranians see the Alawites as a quasi-Shiite regime. (Incidentally, this is why the Shiite prime minister of Iraq has also been somewhat supportive of the Syrian regime, an irony for those expecting him to support the American – or the humanitarian – position.)

The Russians and Chinese, meanwhile, support the regime as much as anything because they don’t believe the West should have the authority to topple regimes it doesn’t like. They feel that the West exceeded its mandate in Libya and, most of all, they don’t like the idea of establishing a principle of international law under which if a regime is suppressing its own people, outside forces can come in and topple it. After all, what happens the next time there are protests against the Kremlin in Moscow?

In fact, the Russians don’t really have very deep ties to the Syrians, while the Chinese have almost none. With this in mind, you’d have thought it might be possible to have the Security Council come together and put more pressure on the Syrian regime, something which would then isolate Iran as the lone sponsor of the brutal crackdown. But clearly the Russians and Chinese have dug their heels in.

So, where does that leave us? I’ve always believed that Syria would see a slow, painful burn. The regime will not fall easily and there’s no easy international intervention that that will make it fall. And when it does fall, it is unlikely that we will see a relatively stable transition to a post-al-Assad democratic Syria. Instead, what you’re likely to see is more of the same – a very messy situation that may well resemble the civil war in Lebanon in the 1980s. Then, we had a conflict that went on for years without a clear resolution and left the country to become a staging ground for perpetual violence. I fear the same fate might befall Syria, too.