August 2 - The U.S. Department of Homeland Security and the U.S. Department of State today suspended two programs that allow certain international air passengers to travel through the United States for transit purposes without first obtaining a visa. The programs, known as the Transit Without Visa program (TWOV) and the International-to-International transit program (ITI), have been suspended. The action takes effect at 11:00 a.m., Saturday August 2, 2003. (Note: All times are U.S. EDT). This action does not affect U.S. citizens or citizens from visa waiver countries.

Homeland Security issued instructions to all airlines to no longer allow passengers to utilize these transit programs. Homeland Security agencies are also taking additional steps to increase security at airports and on airplanes that normally transport and process passengers under these programs.

http://www.dhs.gov/dhspublic/

If you (only for Canada PR, not Canadians) planned your trip via US to India or vice versa and you don't have the visa to US then talk to your travel agent to change your travel plans.