>>63978210 (OP)The civil war started by having a massive chunk of The Syrian military defecting to form the free Syrian army (remember when those were relevant?)
So right off the bat Assad lost a big ass chunk of his army.
The population was also only ~11% Alawite despite being the ones in charge, so Sunnis (>80%) were absolutely on board with the fall of Assad.
And then came the various Salafis like al-qaeda (aka Jabhat al-Nusra aka Tahrir Al-Sham) and ISIS as well as regional minorities like the Kurds mobilizing and securing their own lands.
Before Russia got involved Assad was on borrowed time, he couldn't even stop the fall of territories on his own.
And then Russia got involved and demonstrated what an uncontested air force can do, essentially pausing any territory exchange indefinitely.
Years passed and we got
>Russia involved in Ukraine to the point of not being able to afford to invest more into Syria>Iran never sent much beyond fuel, monetary assistance and "military advisors">Hezbollah command got Shalom'd by a bunch of pagersSo Tahrir Al Sham figured "hey, all their sponsors are out, let's try pushing"
They did and they found no one pushing back
So they kept going and the handful of government loyalists standing guard in checkpoints to keep up appearances didn't even bother trying to push back and understandably fucked off.
And they just kept going until they found themselves in Damascus going "lmao what just happened"
TL;DR: Syria's own army at this point was virtually non-existent for years, with the only thing keeping Assad out of Moscow being his allies.
The term "paper tiger" was thrown around a lot in regards to Russia, but Syria was THE paper tiger.
Like an elephant tied to a small stake, the moment the rebels tried pushing when Assad's patrons were preoccupied they realized there was no one there.