Friday night, an FBI Justice Department operation thwarted a mass terror attack in Portland, Oregon, during the city’s annual tree-lighting ceremony.

The terrorist, Mohamed Osman Mohamud, a 19-year-old Somali-born naturalized U.S. citizen, tried to detonate what he thought was an explosive, but was really a fake bomb given to him by undercover FBI agents.

Mohamud, who grew up in Oregon, not far from Portland, was arrested on accusations of attempting to use weapons of mass destruction, which carries a maximum sentence of life in prison and a fine of $250,000.

This foiled terror attempt is the latest in a sequence of attacks planned by U.S. citizens – the Fort Hood shooting, by Virginia-born Nidal Malik Hasan (November 2009), the Times Square bomb attempt, by naturalized U.S. citizen, Faisal Shahzad (May 2010), and the cargo planes bomb plot, planned by New Mexican-born Anwar al-Awlaki (October 2010).

Additionally, Al-Awlaki has inspired and designed other attacks within the United States, including Umar Farouk Abdulmutallab’s attempt to detonate explosives hidden in his underwear on a Northwest Airlines flight last Christmas (December 2009).

The timing of Friday’s bomb plot, Thanksgiving weekend, is symbolic as it is when Americans transition from a celebration of gratitude and unity, to the holiday season, a time of family and goodwill. This follows in the pattern of last year’s foiled Christmas Day attack – threatening Americans when we are busy celebrating.

When reminded prior to the attack by undercover FBI agents posing as co-conspirators, that many children would be present at the event, Mohamud responded that he wanted to kill a “huge mass of people…[celebrating the holidays] with their families”.

Mohamud’s intentions are a glaring reminder of the threat of homegrown Jihad. There are American citizens that are resolute in their objective and motivation to kill fellow Americans and to target our value system even as we come together in festive holiday spirit.