AMNA NAWAZ: Welcome to the "News Hour."

After 13 brutal years of war, Syrians breathed free today in Damascus and most of the nation after the fall of the autocratic Assad dynasty.

GEOFF BENNETT: Bashar al-Assad and his family are now in Russia, which extended them asylum.

The lightning-fast seizure of the nation by insurgent forces over the last two weeks rocked the region and the world.

But for many Syrians today, the task after the fall of Assad was to take stock of the catastrophic damage done by over five decades of their rule and what the future holds.

Nick Schifrin starts our coverage.

(CHEERING) (CHANTING) NICK SCHIFRIN: In free Damascus today, the foot soldiers of revolution celebrated the birth of a new nation and a new generation that will barely know a ruler named Assad.

Syrians who have known nothing but Assad called today victory and flew the flag of the Syrian republic, now the flag of free Syria.

DR. SAEED KHALIFEH, Pediatrician (through translator): This great and glorious day is the new independence day of Syria.

MOUNIR AL-GHARIB, Damascus Resident (through translator): People are delirious with happiness here.

Yesterday was a great day, and we are waiting for the country's children to return home to enjoy it.

NICK SCHIFRIN: The country that millions fled, now tens of thousands of cars, tens of thousands of families returning to their homes, even if those homes no longer stand.

Yaser Shehadeh and her husband haven't seen their destroyed neighborhood since the war began.

YASER SHEHADEH, Displaced Syrian Refugee (through translator): Now, after 13 years, we are back and the joy is overwhelming.

Thanks to Allah, we are home again.

NICK SCHIFRIN: For nearly a decade, this was Syria's map, the opposition in green cornered in Idlib province in Northwest Syria, the Kurds backed by the U.S. in yellow in the northeast, the regime and its allies in red with pockets of desert controlled by the Islamic State in purple.

It was redrawn in just 10 days, the opposition sweeping through Aleppo, Hama and Homs, and seizing Damascus with barely a shot fired.

U.S. officials say their top concern, keeping those ISIS pockets frozen.

Yesterday, the U.S. launched a large air raid into Syria, bombing 75 different targets described as ISIS meetings and training.

Syria's neighbors are worried about instability, and Israeli officials told "PBS News Hour" that ground forces in blue entered Syria for the first time in more than 50 years to create what they call a buffer zone in what has been demilitarized territory along the Syrian border.

Israel also targeted suspected chemical weapons sites and long-range rockets to prevent them from falling into rebel hands.

Yesterday, Israeli Prime Minister Benjamin Netanyahu visited the Golan Heights and took credit for ousting Assad.

BENJAMIN NETANYAHU, Israeli Prime Minister (through translator): This is a historic day in the history of the Middle East, a direct result of the blows we inflicted on Iran and Hezbollah, the main supporters of the Assad regime.

This created a chain reaction throughout the Middle East of all those who want to be freed from this regime of oppression and tyranny.

NICK SCHIFRIN: Oppression was an Assad family affair.

Hafez al-Assad Assad and his son Bashar ruled the country for 52 years.

He and his wife, Asma, claimed to be Syria's stylish modern future.

But, in 2011, as part of the Arab Spring, pro-democracy protests swept through the country.

Assad unleashed a brutal crackdown that triggered civil war and left cities in ruins.

Half the country, more than six million people, fled their homes, desperately making a dangerous journey by boat because the land was no longer safe.

But so many, including 3-year-old Alan Kurdi, never made it, this image becoming the icon of fear and flight from Syria.

Those who stayed to fight and whom the regime caught disappeared into Sednaya, a notorious military prison outside Damascus.

Some were tortured so severely, the only word he can say today is Arabic for Aleppo, the prison the crucible of Assad's cruelty, the bodies that embody Assad's brutality.

Now Assad stands no longer, his legacy smashed, his stature diminished.

His army retreated, hollowed out by years of corruption and defections, and Assad's previous saviors, Iran and its allied militia Hezbollah and Russia, unwilling and or unable to save him.

Syria's new apparent leader, Ahmed al-Shar'a, better known as Abu Mohammad al-Jolani, met today with the prime minister.

Jolani vows a smooth transition and moderate governance to respect minorities.

But he and his group, Hay'at Tahrir al-Sham, or HTS, are designated by the U.S. as foreign terrorists.

Whether they govern for all Syrians, whether this country's splinters is unknown.

But, for now, these Syrians enjoy a new day of freedom and hope the future brings peace.

For the "PBS News Hour," I'm Nick Schifrin.