Not unless you posted it on reddit. Did you post it here somewhere?
I donl't think you can say it has a time scale other than how long it takes for a society to grow so comfortable and relaxed the people forget what hard times were and how to cope with them, and their leaders are those who would be unfit to lead in hard times because they can't make tough decisions and aren't very strong of will. I don't think you can say the US civil war was caused by the soft men who had years of prosperity because I don't think the US was very 'soft' during this time due to western expansion and Indian wars. Not to mention it was still a society marked by little support for the poor or sick. You made your own way in life and your own success or died and no one cared which.
But I do think we're now in very soft times and have been for the last thirty years or so. Real poverty and hardship is gone, and stability and security ensure almost no one ever knows real fear of violence. When universities have to offer therapy counseling for students because a speaker will be coming on campus to say things which are politically incorrect, you know these are soft people. Can't find a job? Don't like the jobs available? No problem. The state will give you some money! Our ancestors came to Canada in wooden boats in hopes of the hard work of a farmer, where they had to clear the ground by hand first Now we have to bring in temporary foreign workers for fish plants because people think the work is unpleasant and would rather stay home and collect pogey. If there were fighting in the streets in Canada the first people who would be overwhelmed would be the therapists.
Which would be okay if no challenges lay ahead, and other nations were similar, but we know there are, and we know they aren't.