US Secret Service - the United States intelligence agency that protects current and former presidents and vice presidents and their immediate families and protects distinguished foreign visitors; detects and apprehends counterfeiters; suppresses forgery of government securities and documents.
It's  blessings not blessing.. The entire clause is ...to secure the  blessings of liberty to ourselves and our posterity....    The blessings of liberty refers to all of the benefits that are  afforded by having liberty.
Land that we love, our Sierra Leone. ##### One with a faith that wisdom inspires, One with a zeal that never tires; Ever we seek to honour thy name, Ours is the labour, thine the fame. We pray that no harm on thy children may fall, That blessing and peace may descend on us all; So may we serve thee ever alone, Land that we love, our Sierra Leone.