It is true that Nigeria was once a British colony. However let us look at the facts, Nigerians wanted to regain control of the country and it's
citizens. Britain finally handed Nigeria back to Nigerians.
Naturally the rules of the game now changed. When someone wishes
to visit you and stay in your home, you try to find out about as much
as you can about them before you agree to letting them stay with you.
If you feel, uncomfortable, you are likely to say no.
I am glad that people must apply for Visas to come to Britain. There are some criminals out there who would enter the country, cause some damaged and give Nigeria a bad name, if they are allowed to come and go as they please.
Law and Order has to be maintained at all costs. This does not just apply to Nigeria and Britain but to the whole world.