Original sentence: The North Atlantic Treaty Organization (NATO; , )); ), also called "the (North) Atlantic Alliance", is an intergovernmental military alliance established by the signing of the North Atlantic Treaty on 4 April 1949
Edited sentence: The North Atlantic Treaty Organization (NATO; , )); ), also called "the (North) Atlantic Alliance", is an intergovernmental military alliance based on the North Atlantic Treaty which was signed on 4 April 1949