What was the Patriot Act and why did many Americans feel that it was a violation of civil liberties?

Patriot act was brought in 2001 just after the Terrorist acts in New York to prevent similar things to happen. People believed that is violating their civil liberties because it enabled American government to monitor phone calls, mails even financial transaction of its citizens.

Explanation:

After the 9/11 events American government led by George Bush wanted to make new changes while fighting terrorism. One of those ways was introduction of Patriot Act, that spread the definition of terrorism, putting emphasis also on domestic terrorism.