This was no “one off,” as Homeland Security Secretary Janet Napolitano so memorably described the young bomber who nearly blew up his plane over Detroit last Christmas.

This was a “network,” a “deadly pipeline,” said Attorney General Eric Holder as he unsealed four terrorism indictments against 14 people, most of them of Somali descent, including several American citizens, charging them with funneling funds and fighters to the Somali terrorist group, Al Shabab.

This was also the Justice Department’s most serious public response to date to counter a threat that has been growing in the far-flung states of Minnesota, Alabama, and California.

Finally, this was an “unmistakable warning” to others considering joining or supporting terrorists groups like Al Shabab Holder solemnly intoned – “If you choose this route, you can expect to find yourself in a U.S. jail cell or a casualty on the battlefield in Somalia.”

Al Shabab, which means “the youth,” or “the kids” in Arabic, has never staged a terrorist attack in the United States. But they are not the harmless juvenile delinquents their name implies.

Their calling card is beheading, and they are known throughout Africa for the ruthlessness of their tactics.

Their latest attack, for which they were brazen enough to claim credit, was killing scores of innocents soccer fans in Uganda’s capital who had gathered to watch the World Cup soccer match.

The group also has close ties in its brotherhood of terror with Al Qaeda.

Interestingly, Holder would not rule out a possible connection between some of those indicted today and the bloody Uganda soccer attack.

Holder also stressed that Al Shabab’s victims were “innocent Muslims,” eager to discredit the romance that going off to the old country to fight Ethiopians or their evil central government might hold for potential recruits.

Clearly, there is a radicalization threat in the refugee communities of Minneapolis, now home to roughly 34,000 Africans, many of them Somalis who speak little English and are particularly in danger of succumbing to such patriotic appeals.

There are three striking elements of the government’s charges today. First is the indictment of two American citizens thought to now be fighting in Somalia.

One of the two, Omar Shafik Hammami, 26, turns out to be a major player in Shabab – a hip-hop recruiter whose appeals in English to join the group are widely seen by vulnerable young Muslims in America and other countries.

In one popular video, he can be seen in an infantry-like crouch, rapping about the joys of killing “kafirs,” unbelievers, as video images of people shooting and dying are seen as a backdrop to his prose.

Hammami turns out to have a New Jersey connection – the two young Jersey boys who were recently arrested and accused of trying to fly to Egypt to join Al Shabab and fight in Somalia, or against their own country, were aficionados of Hammami’s YouTube tapes. He was one of their favorite clerics, they told investigators – one of the holy men who had prompted them to join the cause.

But Hammami is even more than a propagandist: he is one of the only people in the group to be charged with being a senior Al Shabab member – with “operational responsibilities.”

The second new twist is the indictments of Hawo Hassan and Amina Ali, who were brazen enough to pass themselves off as simple charity workers trying to help Somali poor people in interviews on Minnesota Public Broadcasting last year.

They were terrorist supporters hiding in plain sight. Ms. Ali, in particular, told other participants in a fundraising teleconference in 2008 that they should “forget about the other charities” and focus on “the jihad.” So much for those poor starving Somali orphans.

The day after she was questioned by the FBI, she contacted an unindicted co-conspirator to warn them that she had just been “questioned by the enemy here.”

Some of those charged today may have been impressionable young people, but Ms. Ali is 33; Ms. Hassan, 63. Both are old enough to know better.

The indictments reflect the value of the law barring such “material support” for terrorist groups like Al Shabab.

And they also show the importance, as Eric Holder also noted today, of cooperation from Muslim-Americans who are outraged and frightened by the wave of radicalization that has overtaken so many young people of their faith.

Holder thanked in particular, the Muslim community of Minnesota, without whom the conspiracy might not have been discovered.

That cooperation is worth contemplating as we debate whether or not there is a place for a Muslim community center to foster interfaith tolerance near Ground Zero in New York.

Judith Miller is a writer, Manhattan Institute Scholar and Fox News contributor.

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