The end of the Cold War intensified hopes for increasing international cooperation and strengthened international organizations focused on approaching global issues . This has paved way for the establishment of international agreements such as the Organization for the Prohibition of Chemical Weapons , the Universal Declaration of Human Rights , the Convention on the Prevention and Punishment of the Crime of Genocide , and the Paris Climate Agreement . Environmentalism has also become a mainstream concern in the post-Cold War era following the circulation of widely accepted evidence for human activity 's effects on Earth 's climate . The same heightened consciousness is true of terrorism , owing largely to the September 11 , 2001 attacks in the United States and their global fallout
September 11 , 2001 attacks
September 11 attacks
Post–Cold War era