What law did Congress pass shortly after the 9/11 attacks that dramatically expanded the federal government's ability to investigate Americans without establishing probable cause for "intelligence purposes" and to conduct searches if there are "reasonable grounds to believe" there may be national security threats?

Patriot Act

Explanation:

The Patriot Act, originally known as USA Patriot Act, was signed into law by U.S. President George W. Bush on October 26, 2001.

The Patriot Act was proposed and signed into law following the 9/11 attack, the purpose is to, arm law enforcement with new tools to detect and prevent terrorism.

Basically, the Patriot Act whose purpose is to preserve life and liberty, tends to improve the Americans Counter Terrorism Efforts through the following ways:

1. The Patriot Act allows investigators to use the tools that were already available to investigate organized crime and drug trafficking.

2. The Patriot Act facilitated information sharing and cooperation among government agencies so that they can better "connect the dots."

3. . The Patriot Act updated the law to reflect new technologies and new threats.

The title of the Act which is USA PATRIOT for Uniting and Strengthening America by Providing Appropriate Tools Required to Intercept and Obstruct Terrorism Act of 2001. It was created or coined by 23-year-old Congressional staffer Chris Cylke.

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