The origin of these attackers demonstrates that the threat is more diverse than eight countries that the Trump Administration has focused on in promoting its travel ban, which initially included Chad, Iran, Libya, Syria, Venezuela, Yemen, Somalia, and North Korea.

Get the think newsletter. This site is protected by recaptcha

And yet, the majority of Central Asian Muslims are not jihadi terrorists; on the contrary, many are moderate or secular. Christians, Jews, and Muslims have co-existed for centuries in the region. But, after the collapse of the Soviet Union, which punished the observance of every religion, the locals re-discovered their Islamic roots, and today the level of observance varies from strict in the villages to lax in the big cities.

Many Uzbeks once joined their ethnic brethren in the ranks of the Northern Alliance in neighboring Afghanistan to fight against the Taliban before 9/11; more recently, however, Uzbeks swarmed the ranks of al Qaeda and ISIS, as well as the Islamic Movement of Uzbekistan, a terrorist organization aimed at subverting all of the governments of Central Asia.

Beyond those organizations, the Muslim Brotherhood (which originated in Egypt and has branches of adherents in many other countries, including Hamas in the Gaza Strip) and Hizb-ut-Tahrir (a secretive global organization that strives to overthrow existing regimes and re-establish the califate, a militant theocratic state) have both been active in the region.

However, when ISIS began its bloody takeover of parts of Iraq and Syria, thousands from the former Soviet Union answered the self-styled caliphate’s call, and Russian became the third most common language among the jihadis in that region, after Arabic and English.

Sayfullo Saipov is from a far-away land many Americans haven't heard about. Google

Now that Raqqa has fallen, these ISIS “foreign fighters” — as well as radicalized fellow travelers — have seemingly begun following the pattern seen in Nice, France and Berlin, Germany in 2016: using trucks as weapons.

Which brings us back to Saipov and his alleged attack on New York City: U.S. authorities will have to drill deep to analyze the Saipov case and its circumstances. They still aren’t sure how he was radicalized, and by whom, though they currently suspect self-radicalization. Law enforcement currently says that he was not being monitored or under surveillance, though he may have contact with people who were.

But more broadly, to address the risks and investigate the origins of this attack, the U.S. law enforcement and national security community need a capability they currently lack: an in-depth knowledge of the Islamic religion, as well as history, geography, and politics in the regions beyond those stereotypically associated with terror, post-9/11. A program to address this systemic failure of expertise is long overdue, especially after the Boston Marathon bombing.

And, while we need to preserve our liberties and individual rights, domestic intelligence work, including within closely-knit immigrant communities, in mosques and Islamic centers, needs to improve. What Saipov and people like him are doing casts a dark shadow over the whole American Muslim community, and twists the intention of faith, so Muslim leaders and clergy in the U.S. need to send the broadest anti-extremism messages to their communities.