The attacks had multiple, far-ranging effects. Besides the immediate impact on the victims and their families, the attacks caused widespread anger among the Indian public and condemnation throughout the world.

The immediate impact was felt on Mumbai and Maharashtra state, and throughout urban India. There were also after-effects on the Indian government, center-state relations within India, Indo-Pakistani relations, domestic impact within Pakistan, on the United States's relationships with both countries- the US-led NATO war in Afghanistanand on the Global War on Terror.

The War on Terror (also referred to as the Global War on Terror or Global War on Terrorism (GWOT)) was a common term for the military, political, legal and ideological conflict against what the effort's leaders describe as Islamic terrorism and Islamic militants, and was specifically used in reference to operations by the United States since the September 11, 2001 attacks.

The stated objectives of the war are to protect US citizens and interests in the US and abroad, break up terrorist cells in the US, and disrupt the activities of the international network of terrorist organizations made up of a number of groups under the umbrella of al-Qaeda.

Both the term and the policies it denotes have been a source of ongoing controversy, as critics argue it has been used to justify unilateral preemptive war, human rights abuses and other violations of international law.