MELISSA BLOCK, HOST:
Religious belief is getting weaker in North America, Europe and parts of Asia, but people everywhere else are as devout as ever and Islam is gaining strength. Muslims are now the fastest-growing religious group in the world. Those are some of the findings from a new report from the Pew Research Center. Here's NPR's Tom Gjelten.
TOM GJELTEN, BYLINE: Anyone who advocates a war on Islam should consider the numbers. By the middle of this century, there will be about 2.8 billion Muslims in the world, up from 1.6 billion today. That's the estimate from the Pew Research Center. About 20 years after that, Muslims will outnumber Christians worldwide. Largely, this is for demographic reasons.
ALAN COOPERMAN: Muslim populations are concentrated in some of the fastest-growing parts of the world, specifically sub-Saharan Africa, the Middle East, North Africa and parts of Asia, specifically South Asia.
GJELTEN: Alan Cooperman is Pew's director of religion research.
COOPERMAN: Consequently, Muslims who make up big parts of the population in those areas are growing as a share of the world's population. It's not primarily driven by people switching from something else to Islam.
GJELTEN: Not about people converting to Islam. In the most developed parts of the world, where more people are losing their religious affiliation, birth rates are lower. In the less-developed parts of the world where almost everyone still identifies with a faith tradition, birth rates are higher and populations are growing. Islam in particular benefits. Another development highlighted in the Pew report is migration - people on the move. Many Muslims are heading to North America and Europe. The result, Alan Cooperman says, is that the Christian share of the population in those countries is steadily shrinking.
COOPERMAN: For example, in the United Kingdom, nearly three quarters of people in the U.K. are Christian. By 2050, we estimate that it'll be down to just under half, about 45 percent. Similarly, in France, about 63 percent of France's population is Christian today. By 2050, we estimate that it'll be 44 percent.
GJELTEN: Muslims by then could make up about 10 percent of the population in Europe. In the U.S., they will outnumber Jews and be the largest non-Christian group. The prospect of Muslims becoming the largest religious group in the world may alarm those who see a developing clash between Islam and the West. But Professor Amaney Jamal of Princeton University, herself a Muslim, says if more Westerners now encounter Islam, conflict actually be less likely.
AMANEY JAMAL: To a large extent, this idea of a civilizational divide is really an opinion harbored by those who really know very little about Islam and have had very little contact with Muslims or with the religion of Islam.
GJELTEN: With Islam as the fastest-growing religion in the world, Muslims and non-Muslims will be more exposed to each other.
JAMAL: And where we've seen contact and socializing and getting to know one another, things are a lot better.
GJELTEN: But integration is critical, Jamal says, especially in Europe. If the fast-growing Muslim minority there becomes a social and economic underclass, the conditions may be ripe for unrest and radicalization. Tom Gjelten, NPR News, Washington. Transcript provided by NPR, Copyright NPR.
