In the article, the author discussed the difficulty that the United Nations had in drafting a definition of terrorism. Why was there so much disagreement on the issue?

2,3,4

The definition contains three key elements: 1. the essence of the action (deliberate use of violence); 2. the underlying goal (achieving political ends); and 3. the object of the attack (civilian targets). The first two elements are largely (though not entirely) accepted elements of most definitions of terrorism.