Many new security measures have been established in the United States since the September 11, 2001, attacks. Police 11 their searches of people and their belongings as they enter government buildings and other places. For example, security guards at popular monuments like the Statue of Liberty are searching visitors more carefully. Visitors' bags 12 electronic devices. Also, tours of the White House have been cancelled as a result of security fears. Even the streets in front of government buildings like the Independence Hall National Park in Philadelphia 13 drivers. Across the country, police are setting up checkpoints outside of airports. For instance, police inspect vehicles at several key points on highways 14 Bush International Airport in Houston, Texas. The police stop drivers and ask them to open their car trunks. Even visitors to Disneyland and Disney World are stopped at the entrance gates. Police open their bags and look through them. All these security measures are being taken to prevent bombings and other acts of violence. However, they make life less convenient for many Americans.