FYI - a technical leader and top subject matter expert in a given field does not need to have a doctorate in linguistics and/or English to be able to design the best technologies, write the best codes, and perform the best
Look around, outside the US, and see who are the best and highest ranked researchers, H-index >60 (if you know what that means), and try to find the distribution globally as a function of country or researcher origin. You do not need to a native speaker of a particular language.
The same is true for me, I do not care and will not spend a single minute leveraging my writing or speaking skills in English. I came here to serve this country long time ago, and have worked with really awesome people, but also came across nasty group of people like those who posted below. I am already successful, ranked among top 10% in the U.S. from an H-index prospective, and probably have achieved 10x more than any of you here who have been trying to funny. So, with that said, yes - the previous responses here gave me an indicate about the overall behavior of some people, however it was not the only reason behind my decision (I've already met several people internally, met them virtually, spoke with them, and made my decision based on whatever I felt is the write choice).
Take away: Never ever try to judge someone based on his origin or English skills, etc.. those things do not matter in many fields, specifically the technical ones. You have proven to yourself and others that you still think like a 10-years old kid.