Syrian boys sit on a street after an airstrike July 9 in the northern city of Aleppo. / Fadi Al-Halabi, AFP/Getty Images
GAZIANTEP, Turkey - After more than three years of civil war in Syria, government troops are advancing to retake Aleppo, the country's largest city, and possibly deliver a crushing blow to the rebellion against the regime of President Bashar Assad.
Defeating the rebels would give Assad a major victory as he prepares to be sworn in for a third term next week.
"It will be a huge loss for the revolution if Aleppo falls, as it became the biggest stronghold for the rebels after the fall of Homs," said Baraa al-Jabli, 20, of Aleppo, who works with the opposition.
Assad's gain would also be a loss for President Obama, who has called for the Syrian president to step down, citing mass atrocities against his own people, so new elections can be held. Obama recently proposed $500 million to aid more moderate rebels in southern Syria, a move that follows complaints by Sen. John McCain, R-Ariz., and other critics that the president has been too timid in supporting the rebellion.
This week, both sides began preparing for what could be a fierce battle in Aleppo, the last urban area that Syrian rebels partly hold. If the rebels are ousted, that could end the uprising that began in March 2011 against Assad's rule and quickly turned into a civil war that has killed more than 100,000 civilians.
The Islamic Front, a coalition of rebel groups, has called for reinforcements to defend the city, sections of which have been held by rebels since 2012.
Oubai Shahbandar, a spokesperson for the Syrian National Coalition, said Assad's forces are "almost entirely dependent upon Iranian military forces and Lebanese Hezbollah militias."
The Britain-based Syrian Observatory of Human Rights, an opposition-affiliated organization, said military reinforcements are arriving from Iran's Republican Guard and from Lebanon's Hezbollah to cut the rebels' supply lines.
"Syria is really its four big cities. If (Assad) can retake Aleppo - the last big city contested by rebels, he will feel that he has destroyed the rebellion and retaken Syria," said Joshua Landis, director of the Center for Middle East Studies at the University of Oklahoma.
The rebels not only face Syrian forces, they're also fighting the al-Qaeda splinter group called the Islamic State, which recently pushed into the Syrian countryside surrounding Aleppo. Last month, the militant group claimed control of a large part of Iraq and parts of Syria to create an Islamic territory that straddles both countries.
"We have Assad in front of us and (Islamic State) behind us - what can we do?" said Abo Yussef of the Liwa al-Tahwid brigade of the Islamic Front in Aleppo.
Holding the line against the Islamic State farther north in the province is tying up troops and splitting the rebels' limited military presence, he said.
In Aleppo, rebels struggle with their limited weaponry, said Col. Abu Bilal, military commander for Liwa al-Tahwid.
"Everybody knows the rebels don't have high-quality weapons," he said. "We don't have enough ammunition. Aircraft and the airplane normally fly very high and bomb."
Rebel groups, however, are increasingly coordinated, he said. "We have a strategy to stop them surrounding Aleppo," he said. "I think it will be a long battle."
The $500 million in aid proposed by Obama last month to train and arm the Syrian opposition would go to approved rebel groups as part of a larger effort to protect U.S. allies in the region - Jordan, Turkey, Iraq and Lebanon - from a growing threat of Islamic extremists fighting the Syrian regime.
Obama unveiled the plan amid a series of internal problems within the military arm of the Syrian National Coalition - a sign of the difficulties within the opposition and the constant frustrations facing Western nations that have attempted to aid the rebels. Obama has said Western support is complicated by concerns that moderate rebels get the help, not the extreme groups such as the Islamic State.
The rebel coalition renewed its calls for arms as a way to stop Assad and thwart the extremists.
"The Syrian opposition has made clear to the international community and its allies that an immediate infusion of military aid is necessary to stop (Islamic State) terrorists from spreading and to halt the Assad regime and Iranian-backed militias from creating a humanitarian disaster on an unprecedented scale," Shahbandar, the coalition spokesman, said.
The threat posed by the Islamic State remains clear in the minds of Syrians who lived under its brutal rule for the latter half of 2013 before pushing the militants toward the eastern part of Syria.
The Islamic State claims it's building an Islamic territory, "but it is hurting people," al-Jabli said. He said civilians have been executed for not observing Islamic religious customs.
For rebels, the battle is not just for control of the city, it's a fight for survival. Most of those in the rebel-held part of the city simply have nowhere else to go. After months of relentless bombing in Aleppo by government forces, a pre-election campaign by the Syrian government allowed those remaining the option to be "pardoned" and return to government-controlled areas.
For many, this isn't an option.
"The fighters' willingness to fight is at an all-time high," al-Jabli said.
Contributing: Mohammad Haj Ali in Amman.
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