From Richard Flanagan's The Narrow Road to the Deep North, which I am reading now, it is obvious that the Japanese Imperial Army (JIA) weren't kind employers. Prisoners of war (POWs) were required to work all days of the week in gruelling shifts of twelve hours a day to build what was known as the Death Railway to Burma.
It also appears that when my uncle Cherian Mathew joined the Indian National Army under Subash Bose he might have imagined being treated better than the POWs. But I have a suspicion that he wasn't and the JIA meted out the same treatment as the POWs to the members of INA. There have been eyewitness accounts of how my uncle died of hunger and malnutrition, working in dire conditions. I guess he must have been working on the Death Railway project which sought to connect Thailand to Burma through thick forests. The Bridge over the River Quai is a poignant movie that documents the trials of the prisoners.
In Flanagan's novel the author recounts the experience of Australian POWs working under Japanese supervision. Their boss Nakamura is strict and relentless. Workers are dying around him of malnutrition and cholera, but he shows no concern. He is bound only by the code of honour of serving the emperor, unflinchingly, unquestioningly. He is only worried about meeting his deadlines for the construction of the railway.
It also seems that the Death Railway was built in patches, not end to end. Meaning several gangs were working on different sites, which then would be joined to create the final railway line.
I trolled the maps to find the attached one of the Death Railway. However, on following it to the Burmese border I find that it terminates at a station named Nam Tok and doesn't proceed any further than that. It falters, then comes to a dead end there. So, the railway to Burmah through thick forests was a failure after all. So much effort, starvation, deaths, ill treatment, all happened for nothing.
Now if you search Death Railway on google maps, you will find that the line is dotted by many resorts. I guess, the Thai government must be exploiting the tourism potential of the Death Railway, which happens to be the only saving grace of this wasted effort.