The U.S. is marking the 18th anniversary of the Sept. 11, 2001, terrorist attacks on Wednesday as it has in past years, with solemn ceremonies, mourning, volunteering, and reflection. President Trump attended an event at the Pentagon, followed later by former President George W. Bush. Vice President Mike Pence spoke at the Shanksville, Pennsylvania, memorial, and family members of the nearly 3,000 people killed in the attacks on New York City's World Trade Center towers gathered in lower Manhattan. For the first time this year, the World Trade Center site has a memorial dedicated to the first responders and others "whose actions in our time of need led to their injury, sickness, and death."

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