Ayham Kurdi refused to open fire on unarmed protesters and is now an enemy of the Syrian state.
A captain in President Bashar al-Assad's army, Kurdi, 30, a soft-spoken man with a trimmed black moustache, deserted his post in June and fled to neighbouring Turkey with his family.
He is now a member of the Free Syrian Army, a loose collection of deserters who are fighting to topple Assad.
Other Free Army officers have taken refuge in Turkey as well, including the group's most senior commander, from where they communicate and coordinate operations with rebel units inside Syria.
I left because of the massacres of civilians in Syria. Every day the regime is killing up to 30 people in Homs and sending tanks to the streets, he said, referring to the city that has become the focus of protests against Assad.
Speaking to Reuters over thick dark coffee in the house of a Syrian émigré in the southern Turkish city of Antakya, Kurdi said the Free Army needed more weapons and equipment, and that foreign intervention might be needed to prevent Syria from descending into civil war or a drawn-out conflict.
If there is no foreign intervention and the international community does not step in to assist Syria, the situation is unlikely to change and the regime can last for a long time, he said.
If Arab states fail to stop a bloodbath it would be an obligation for Europe and the U.S. to intervene militarily. We prefer a diplomatic solution but if this fails we would want a military intervention. This could take the form of a no-fly zone and a buffer zone, Kurdi said.
Like most of the military, Kurdi is a Sunni Muslim; but the command is in the hands of officers from Assad's Alawite sect, an offshoot of Shi'ite Islam that also dominates the security apparatus and ruling elite in the majority Sunni country.
He said more and more mid and lower-ranking units were defecting to the Free Army, which rebels say numbers about 10,000.
In the first months of the revolt there were fewer desertions but the number has significantly increased in the last 10 days to a month. Five days ago in a military base in Deraa, 20 soldiers slipped guards a sedative, then stole all the guns and fled.
Based on recent movements by government tanks and troops, he said he feared Assad might be preparing to launch a large-scale onslaught in Homs, in nearby Hama or in the coastal towns of Latakia or Tartus.
But this would only galvanise more opposition across Syria, he said. The United Nations says more than 4,000 people have been killed since protests began in March, inspired by the Arab Spring uprisings which have toppled autocrats in Tunisia, Egypt and Libya.
If they enter to crush Homs it will be a big mistake. It will trigger a reaction across the country. There are rumours the regime is moving the Alawites away from Homs in preparation for a major crackdown.
Another defector who lives in one of six refugee camps set up by Turkey to accommodate more than 8,000 Syrians painted a picture of low troop morale in the rank-and-file, who are forced to follow orders from commanders or face reprisals.
They ordered us to deploy in Deraa and open fire on people who were causing trouble. But when we got there they were just protesting and they had no weapons, said Ahmed, who fled in August and is from Hama.
Many people feel the same way I do. If you are in the army you do what you are told, you follow orders to shoot and kill. Many soldiers don't want to do this but if they desert they fear for their families. If you leave the army they can take your mother or father to prison.
Turkey's decision to offer safe haven to the Free Army along with blunt calls by Turkish Prime Minister Tayyip Erdogan for Assad to quit have shattered once close ties between Ankara and Damascus. Damascus says the rebel soldiers are traitors serving the enemies of Syria.
The group's top commander, Colonel Riad al-Asaad, is staying along with 60-70 officers in a refugee camp at Apaydin, some 10 miles from Antakya and close to the Syrian border.
Turkey closely monitors Colonel Asaad's movements. He is not allowed to receive visitors without authorisation from the Turkish government. A Reuters crew was warned not to stop its vehicle near to where he was camped.
From outside, the camp, which is surrounded by trenches, fences and Turkish military outposts, offers a more serene atmosphere than violence-plagued Syria.
It lies in a plain that is home to cotton fields and olive groves, flanked by snow-capped mountains. Cows and sheep graze nearby.
No weapons are allowed in the camp. Defectors dress in civilian clothes and live with their families.
We are taking precautions for Asaad's security, a Turkish diplomatic source said.
Not even an envelope-opener is allowed in the camp. If anything happens to him we will face accusations that Turkey allowed his assassination. The Syrian intelligence is trying to reach that end.
The rebels say they want to avoid a civil war in Syria, and that their main goal is to disrupt military convoys, attack security police and intelligence complexes involved in the crackdown and to defend civilians from repression.
There have been a few operations against intelligence service buildings because they are the tools the regime uses to kill civilians. These centres house Shabiha militias (state-backed paramilitaries) but the main focus is to cut supply lines of convoys. We don't fire at tanks that do not open fire on civilians, Kurdi said.
The regime has tried from the beginning to start a sectarian civil war. But we want to avoid it. We are telling the Alawites to denounce the regime so they don't end up paying the bill.
Kurdi, who lives with his wife and three children, says he stays mostly indoors in Antakya, a frontier city where family and cultural ties with Syria transcend political borders and where Arabic language flows as freely as Turkish on the streets.
Kurdi said he will only return to Syria when Assad is gone. Otherwise, he would be killed.
We are willing to pay whatever the price to end Assad.
(Editing by Rosalind Russell)