You did ask question. Then you answered it your self. If someone disagreed with you you get in defence stance and you get aggravated by that. It is like only your opinion matter. So I do agree with people what said that you described your self basicly.
People migrating from beginning of times. Everyone have right to settle wherever they want if they obey rules and laws of that country. It is strange to here this question from Americans. All of your ancestors migrated to Amerika.
RE: Impolite messages on dating sites
Ignore and report. Many man think they are so awesome and dominant. I don't have this problems because woman have better manners.