Why does IBKR not include Nigeria on the list of countries of residence for application purposes?

√úbersicht: 

Nigeria is one of several countries subject to US government sanctions, money laundering risks and/or other concerns which preclude IBKR from doing business with its residents. If a particular country is not represented on the application list, its residents are not eligible for application consideration.  IBKR does not waive its restrictions in this regard.