Over the past two weeks, as Syrian and Russian warplanes bomb rebel-held east Aleppo around the clock, regime-allied fighters have begun to etch out small advances on the besieged city’s perimeter.

The Syrian army appears to be inching towards its long-standing goal of retaking all of Aleppo city—and thus driving Syria’s insurgency out of high-stakes cities.

But what exactly is the Syrian regime’s strategy in Aleppo? Will the Syrian army launch a ground assault of the city? What do Assad’s backers want?

“My feeling is, if it comes to an assault on the city, what we would see is a protracted battle; the rebels would simply be worn down, wouldn’t be able to sustain that battle or that kind of situation over time,” says Jeffrey White, a defense analyst at the Washington Institute for Near East Policy with more than 30 years of experience studying the Levant and Iran at the Defense Intelligence Agency.

“I’m not saying the regime would simply automatically march to victory in Aleppo," White tells Syria Direct’s Orion Wilcox. “But I think we’ve learned that they keep coming…the regime is very persistent and willing to suffer setbacks.”

Q: Following the collapse of the most recent US-Russia brokered ceasefire on September 28, we’ve seen a massive escalation in the bombardment of rebel-held east Aleppo by the regime and Russia, with Syrian state media reporting a possible ground advance to take the opposition neighborhoods. What is the plausibility of a regime ground invasion of east Aleppo in your perspective? What would that cost Assad?

Anyone following the Syrian war so far would have to believe that a ground fight for eastern Aleppo would be a long and drawn-out affair with lots of casualties.

My original thinking, a month or so ago, was that they probably wouldn’t try to storm the city, at least initially…that they would wait for the effects of the siege and bombardment to wear down the defenders. They may still be tending to follow that strategy.

But if they feel that there is time pressure to take back Aleppo, then an earlier assault on the city becomes more likely.

Q: And in your opinion, what would be the potential impetus for the regime to attempt an earlier invasion?

One consideration might be the willingness of the Russians to continue to support a drawn-out siege. The Russians might not be prepared for the Syrian government to conduct a leisurely siege to slowly wear down the opposition defenses. Especially given the enormous amount of bad press that [Moscow] has gotten recently.

This is war in a fishbowl. The actions of everybody involved are subject to immediate and microscopic examination. So the Russians may not be as patient as Syrians would like to be.

Also, the defeat of the rebels in Aleppo is something the regime might want to accomplish sooner rather than later. This would be yet another demonstration that the regime is not going away, and that it is successfully pursuing its intent to recover all of lost Syria.

Another factor is that holding Aleppo has been in many ways the rebellion’s single greatest accomplishment. The regime might want to remove that from the ledger sooner rather than later.

Q: Are there any precedents that can give an idea of what a ground invasion of Aleppo would look like?

One example of how this would work is the fight for Qusayr back in 2013. There, the regime and Hezbollah forces did in fact storm the city in a difficult battle that turned out to be quite costly in terms of casualties. So that’s an example of how tough this kind of fight can be. But obviously Aleppo would be much more difficult than that.

Q: Holding territory in Aleppo city grants the opposition legitimacy. If the rebels lose more of it, they basically become just a rural insurgency. Do you see any change in the Syrian rebels’ level of morale and fortitude in keeping Aleppo? Do you think that if the regime were to attempt a sustained advance or engage in street-to-street fighting that the opposition’s backers would step back or step up their engagement?

My instinct says the rebels would try and defend the city, and that they wouldn’t abandon it except under dire circumstances. But something I think we’ve both seen in the war is that when the regime decides it wants to take a place or do something, it’s very persistent. It’s willing to suffer setbacks and failures on the road to success.

When I say the regime, I mean all its allies. They’re persistent. And they’re willing to keep fighting and come back even if they had to suffer a setback.

The problem for the rebels is how to deal with that the regime has a significant advantage in firepower and just keeps coming. My feeling is, if it comes to an assault on the city, what we would see is a protracted battle. The rebels would simply be worn down, and wouldn’t be able to sustain that battle or that kind of situation over time.

I’m not saying the regime would simply automatically march to victory in Aleppo. It would be a tough fight and there would probably be some reverses, but I think we’ve learned that they keep coming. That’s a real problem for the rebels.

Q: Do you see any indicators that this reality could shift with regard to manpower shortages or the resolve of the Russians and the Iranians?

People, including me, have been saying for a long time that the regime is running out of people. But they keep coming up with bodies. And as long as the Russians are willing to provide the firepower support, or the Iranians and their allies are willing to provide the bodies, I think we could see this kind of a fight.

When I look at the casualties that the Iranians and their allies have suffered over time, they’re not that great. They’re not losing hundreds of people or thousands of people. They’re losing some. There’s a steady kind of attrition, but to me, it’s not very dramatic.

The willingness of Hezbollah and Iran and so on to continue this kind of fight I think is there, especially if they’re in a situation where they’re being successful, even if it’s kind of a grinding battle of attrition type success. The willingness to stay in that kind of fight is there. Nothing that I’ve seen so far indicates that Hezbollah or the Iranians are ready to quit the war just because they’re losing people. They’re still committed.

Q: I’d like to go back to the first part of your previous question about the fishbowl effect. We’ve seen the regime strategy of encirclement, then offering negotiating terms, then when the negotiations inevitably fall through, tightening the siege, increasing bombardment, coming back with new terms and extracting concessions. We’ve seen that work in places like Darayya and Waer. Like I said earlier, Aleppo is very different.

Is there a threshold within the international community of how much it will tolerate regarding east Aleppo’s 250,000 people? Following the bombing of the SARC convoy in the west Aleppo countryside, we asw somewhat more candid remarks from Europeans and the Americans at the UNSC. How much influence does the international community hold?

Talk is cheap. I don’t think we’re going to see any radical change by the Obama administration. I think there’s a low order of likelihood that Obama will change policy on Syria.

So I don’t think the United States is going to get involved in any kind of serious response to what the Syrians and Russians are doing in Aleppo – what the regime and the Russians are doing in Aleppo.

Q: Is there any chance of the GCC countries or some of these EU countries going it alone without the US?

I think that’s unlikely. Clandestine aid, that’s quite possible. We’d see more anti-tank weapons, more covert military support for the rebels.

But I don’t think we’re going to see any type of dramatic intervention in the conflict. It’s going to be basically up to the opposition military forces to carry on the fight against the regime.

Q: Could there be any kind of change after the US election? That’s what we are hearing people have been waiting for. Is that a realistic expectation?

In four months, the regime could potentially recapture the eastern part of the city.

The problem for the rebels is they don’t have a lot of offensive capability. They were successful in breaking the siege at one point, but the regime was able to reassert that.

So that’s part of what I was talking about: the persistence of the regime. The rebels are, at least in my mind, on the defensive.

I don’t see much that could change that situation as long as the regime military alliance holds together and you still have the Iranian-Russian support. It’s going to be very tough for the rebels, even with some increase in support, to go on the offensive.

Q: There’s been a lot of talk of medieval siege tactics used by the regime and their allies. As someone who has taken a deep look Middle East conflicts in which sieges have been a tactic, how is this war different? Are they all that unique?

That’s a good question. I don’t think it’s been looked at very seriously by anybody. So I’m trying to formulate an intelligent response. This is a siege in a civil war, it’s not comparable to, say, the Israeli so-called siege of Beirut.

It’s not comparable in the sense that the besieging parties were bound by the rules of international law and politics relating to war. This is a civil conflict in which the primary actors in a way are from the same country. Maybe that affects the way the sieges are conducted and are being conducted.

Aleppo might be more like Hama in 1982, which was also part of a civil conflict or Bosnia or Sarajevo, in which the willingness of the besieging power to use all available military means is less restricted.

It may be that there’s a greater expectation that more violence will be used than is appropriate. It’s an internal conflict as opposed to an international conflict.

Q: One reason why the siege of Madaya was much more intense than in other areas is because Hezbollah maintained very tight control of the checkpoints, not allowing food in for bribes.

That strikes me as more of a tactical-level issue.

In the broadest sense, I think what you see is that the regime has demonstrated a willingness and an ability to persist in these siege situations and force them to a conclusion one way or another, either by breaking the will of the population, or by storming and taking an area by force. That’s the broad pattern.

The overall pattern has been a willingness of the regime to use these very medieval tactics to achieve military successes.