Assad dynasty's half century in power
For decades, Saleh has given voice to the people of Syria through his work. In Japan, Saleh travelled to Hiroshima, Kyoto and Tokyo, he spoke about his experiences and how the Assad regime has held power in Syria for more than half a century.
"Syria is a nation controlled by the Assad dynasty and the secret police," he says. "The family is more important than the country. That's why I call it the Assad regime the new sultanic state."
Sixteen years a prisoner
Saleh was a 19-year-old medical student when he was arrested in 1980 for his political activism. He was part of a group that opposed the Assad regime.
One of his best-known books, Salvation O Boys: 16 Years in Syrian Prisons, recounts the 16 years he spent in jail as a political prisoner, vividly capturing his emotional state while incarcerated:
"I resisted and plotted to the best of my ability. But, the more I moved, the more pain cut into my body and left me powerless."
Saleh was held in the notorious Tadmur Prison in the city of Palmyra. The prison came to symbolize the brutality of the Assad regime, with torture a daily occurrence there.
"They either satisfy themselves with slaps on your face — in one minute your face would be swollen and bloody — or they will put people on wheels and flog them and kick them."
Saleh says he had once dreamed of visiting the prison as a free man, but it no longer exists. The Islamic State militant group destroyed it in 2015.
Released to a "big prison"
Saleh was released in 1996 and began writing in the hope that he could change Syria's political situation. But he says he found himself powerless in a surveillance state where critics are at constant risk of arrest.
In Salvation O Boys he likens that so-called freedom to living in a big prison:
"After being released from prison, I realized how much more powerful the system is than we are, and how much we lose ourselves in the world it occupies and controls."
Saleh fled Syria in 2013. The pro-democracy protests two years earlier had spiraled into war, and he felt that his life was in danger.
Shortly after he left, his wife Samira Khali, also a well-known activist, was abducted by a radical Islamist group. She remains missing.
Saleh says he wants his readers to imagine Syria as if it were their country. He says what is happening in Syria is no longer a civil war, as it has become a battleground for a proxy war by other nations.
"People should pay attention and try to understand because Syria is a mirror of the world, something of a microcosm. Through understanding about Syria, they'll understand better the world itself."
Earthquake a crisis within a crisis
Saleh's words resonate even more for the people whose lives were shattered by earthquakes in February. He believes that politics was partly to blame for the extent of the devastation.
"Earthquakes don't recognize national borders," he says. "But the UN recognizes national borders and the logic of sovereignty, and so the help came too little, too late. These unprecedented levels of suffering … It is too much. No human being should be exposed to these levels of suffering."
Staying resolute in exile
During his stay in Tokyo, NHK accompanied Saleh when he met with Syrian exiles to discuss how they could restore freedom in their homeland.
A Syrian man who fled in 2018 asked Saleh, "What can we do to rebuild our country?"
Saleh replied: "The first step is for people to get together and share ideas. If we can gather and speak, we can each protect our own voices. Everyone should be able to go back to their homeland. It may be painful talk about our homeland, but I hope to overcome that pain and return to Syria."
Saleh tells NHK: "I don't submit myself to despair. No one can predict the future. We don't know what will happen in a few days, a few weeks and a few months and few years. There are many, many fighters for democracy in Syria, and in the Arab region and everywhere else. This is what gives me hope. I have to admit still that our enemies are far more powerful. But we'll keep fighting because our backs are already to the wall. We have a saying in Arabic, when your back is against the wall, you have to fight to the end. And I think we'll keep fighting to the end. No matter what."