Whenever a leader is overthrown, a power vacuum is created that can be exploited by self-seeking actors.
The risk is that whoever fills this void will not be interested in peace and reconciliation but in power and revenge.
In Syria, the stunning downfall of the Assad regime brought jubilation to millions of people who had lived under 13 years of on-off civil war and brutal dictatorship.
But it also fragmented Syria's territory, with several armed factions now jostling for control, and international players anxious to preserve their regional interests amid the chaos.
Here's a map showing who controls what now that Assad is gone:
[MAP EMBED]The most powerful group is Hayat Tahrir al-Sham (HTS), which led the lightning offensive against former president Bashar al-Assad, pushing him to flee to allied Russia.
In just days, these Syrian rebels captured the north-western city of Aleppo and then swept southward through Hama and Homs, before seizing the capital, Damascus.
Syria's Assad-era prime minister has agreed to hand power to HTS leader Abu Mohammed al-Golani, who has tried to remake his public image from an Islamist militant to a statesman.
But other opposition groups control parts of Syria and are still in the mix, including two major armed forces.
One of them is a collective of Syrian forces that calls itself the Syrian National Army (SNA), and it controls north-western parts of Syria.
The HTS rebels and SNA forces have been allies at times, rivals at others, and some of their aims differ.
SNA forces, which are backed by neighbouring country Türkiye, have an interest in creating a buffer zone near the Turkish border to keep Syria's Kurdish forces away from it.
This last Kurdish group is known as Syria's Democratic Forces (SDF) and it controls large parts of Syria's north-east.
The Kurds are an ethnic minority group. Türkiye is at odds with the SDF forces, which it says are allied to another group of Kurdish militants that has fought Türkiye for 40 years.
The Turkish-backed SNA forces and Kurdish SDF forces were fighting for control of the strategic northern Syrian city of Manbij, before they reached a US-brokered ceasefire deal.
Regional interests
Israel and its long-time ally the US have been carrying out military operations in Syria but they say they do not want to get involved in the conflict.
Israel says it launched large-scale strikes on military sites across Syria to prevent chemical weapons and long-range missiles from falling "into the hands of extremists".
A military spokesperson said Israeli troops had moved into a demilitarised zone inside Syria, as well as "a few additional points" nearby.
He called the incursion a "temporary, limited" measure to ensure its border security, and denied that Israeli forces had advanced further into Syrian territory.
Meanwhile, the US says it carried out strikes on camps and operatives of the Islamic State to keep the terrorist group from making a resurgence in Syria.
It says some 900 US troops are in eastern Syria, alongside the Kurdish SDF forces, to ensure the Islamic State group does not take advantage of the fallout from the rebellion.
As for Russia, the future of its naval and air bases in Syria remains unclear, though the country says a deal was brokered to ensure the safety of its military bases.
They were used to back Assad and give Russia a footprint in the region. Now, like the rest of the world, it waits to see how Syrians will rebuild their new state.
