Alienated, uneasy, politically up for grabs. Fueled by immigration, they are among the fastest growing voting blocs in the U.S.

Hispanics?  

No: Muslims.

How many Muslims live in the U.S.? A definitive tally doesn't exist in part because the U.S. Census Bureau is prohibited from asking about religious affiliation. (Why?) But estimates range from 2 to 7 million.

If that seems like a wide range—it is. It reflects the conflicting political orientations of the groups making the estimates.

At the low end, 1.9 million, is the "best estimate" of a National Opinion Research Center study commissioned by the American Jewish Congress shortly after 9/11. Muslim groups jumped on the AJC figure as an attempt to "marginalize" Islam in the U.S. [Number of U.S. Muslims Depends on Who's Counting By Bill Broadway, Washington Post, , November 24, 2001]

At the high end a study co-sponsored by the Council on American-Islamic Relations, and released in April 2001, estimated that 7 million Muslims were living in the U.S.

CAIR's methodology was simple. Its researchers simply called the country's 1,209 known mosques, asked their leaders to estimate the number of people involved in any way with the mosque, and multiplied the two figures. The resulting product—2 million—was then multiplied by a factor of 3.5 to capture "un-mosqued" Muslims. 

Predictably, the AJC saw this as an attempt to inflate Muslim population estimates beyond the Jewish population figure, usually put at 6 million in the U.S.

But while the numbers may be in dispute, the trend is clear. Muslims are a rapidly growing slice of the U.S. population—and immigration is the major source of that growth. Compare the growth of Middle Eastern and Asian immigrants with those from the rest of the world over the 1970 to 2000 period: [Table 1]

As a share of the foreign-born population, Middle Easterners rose from 2 percent in 1970 to 5 percent in 2000. This does not include their U.S.-born citizen children, estimated at nearly 600,000 in 2000.

Of course not all Middle Eastern immigrants are Muslim. Back in 1970, about 85 percent were either Christians from Lebanon or other non-Muslims fleeing persecution in Muslim countries.

By 2000, however, nearly three-quarters the estimated 1.5 million immigrants born in the Middle East were Muslim.

Obvious implication: the number of Middle Eastern Muslims living in the U.S. has grown even faster than the overall immigrant population from that area would suggest.

You would think the rising tide of Muslim immigration would have ebbed after 9/11. It did—briefly. But after hitting bottom in 2003, this immigration soared. In 2006 immigrants from primarily Muslim countries—a group that includes South Asians as well as Middle Easterners—represented a larger share of legal permanent residents admitted to the U.S. than in 2000.

The trend is seen in the number of people obtaining permanent resident status (Green Cards): [Table 2]

The number of Green Cards obtained by people born in Muslim countries was 74 percent higher in 2006 than in 2000. Over the same period Mexicans stayed basically the same. The total number of Green Cards awarded rose by 51 percent.

Black Muslims, nearly all of whom are U.S.-born, account for about 30 percent of   the country's Muslims. That translates to about 2.1 million African American Muslims, or nearly 6 percent of all blacks in the U.S.

Black Muslims are reportedly increasing both in numbers and extremism:

"….As African-Americans embrace Islam in growing numbers, many are moving toward a more orthodox version influenced, in part, by Saudi Arabia's puritanical brand of Sunni Islam. These foreign ideas have combined with homegrown black experience to form a mindset that condemns alcohol and drugs and hails self-sufficiency—but one that sometimes also stresses an unsettling hostility to American government and secular society." One Imam Traces Path Of Islam In Black America, The Wall Street Journal,  By Paul M. Barrett October 24, 2003

A Muslim majority? Sharia the law of the land? Even the most wacko Islamist probably doesn't see that happening soon

But Muslim immigration, combined with Muslim proselytizing, could change things quickly.

Edwin S. Rubenstein (email him) is President of ESR Research Economic Consultants in Indianapolis.