I think the thrust of the post is if you dropped out because of personal reasons which are orthogonal to your academics, then you have a chance, but you need to make sure to explain this clearly on your
statement of purpose. If, however, you were asked to leave or decided to leave for academic reasons, like nobody would sign off on your dissertation, then you are in big trouble.
The grey area is if there were personal problems which ate at you, causing a precipitous decline in your scholarly work which ultimately led you to leave. Also, if you were deported for some reason from the US and are no longer allowed back, there may be problems depending on how you spin it and how the adcoms receive it. Since you are being painfully opaque (possibly for good reason,) our collective ability to give you advice is somewhat limited. One observation is that the more clear people make their questions on TM (including background,) the better the answers were on average.
There are a million personal reasons for why an advanced candidate would leave for a time. However, there are only a few good reasons why they are not allowed back in to a previous institution. There are even fewer for why they would choose not to go back if allowed, especially for a top 20 US program.
Trouble with the government is one, but the trouble has to be unrelated to your academic work and out of your control. Administrative troubles are borderline. A perceived poor scholarly potential is bad news.