What are the prospects for someone in the USA who has spent considerable years doing the research but was unsuccessful in defending it?
p.s it can be assumed that the professor was a near-evil person.
The prospects depend on the field and more importantly, depend on the person. I know of many people dropping out of Ph. D. program and being successful; the founders of 2 of the companies I’ve worked for are prefect examples. Failing to get Ph. D. degree doesn’t necessarily mean failing in life.
Assume that the professor was a near-evil person? No, can’t do that without knowing the situation.
I suppose it really depends on the kind of research you were doing, but it’s not necessarily a death sentence. Yes it’s a big deal, but it doesn’t preclude the amount of work you’ve done.
For instance, I currently work at a huge biotech company in San Francisco, and the group leader and senior director of our lab (over 20 people) were both people who dropped out of a PhD program midway to pursue other opportunities.
It also depends on schools. A data point as an example:
http://www41.homepage.villanova.edu/klaus.volpert/PhDStudy/PhD_Study.htm