Most Islamist parties have been gradually gaining supporters for years as secular parties have failed to solve grinding economic and social problems.
But their sudden gain in votes in recent elections in Pakistan, Bahrain, Morocco and Turkey is being viewed as a sign that voters — at least in those few countries that actually allow free elections — want to assert pride in their faith to the outside world.
"The population in Turkey, the population in Pakistan or the population in Morocco did not vote for Islamic parties just because they believe they have the capacity to solve social and economic problems," Muhammad Darif, a professor of political science at the Hassan II University law school at Mohammedia, Morocco, said in a telephone interview.
"Arab and Muslim populations think the war against terrorism is nothing but a war against Islam, the culture of Islam, the Arab culture," Professor Darif added. "The Islamist parties have been able to exploit this."
The recent election results may serve as an opportunity or a risk for the United States, the experts said. They said working with moderate Islamic groups could give Washington credibility it lacks, while opposing them would only fertilize already blooming anti-American sentiment.
"If the U.S. considers anyone who talks about Islam a criminal and pushes the Turkish military to suppress them, it will deprive itself of an ally," said Abdelmonem Said, the director of Al Ahram Center for Political and Strategic Studies in Cairo, speaking of the victorious Justice and Development Party in Turkey.
Although no single pattern fits all four countries, the results in each of the elections gave religiously oriented parties far larger margins than expected.
In Turkey, the winning party is likely to be the first in years to be able to govern without a coalition partner, as it is expected to take more than 360 of the 550 seats in Parliament.
Voters in Pakistan and Bahrain last month also gave religious parties a significant voice in their Parliaments. Islamist candidates took 78 of 392 seats in Pakistan's Parliament, while such parties control about half of the 40 seats in the newly elected assembly in Bahrain.
In Morocco, Islamist groups took 42 of 325 seats in elections in September, up from 14 in the last election.
In Bahrain, most of whose people belong to the Shiite branch of Islam, Parliament — the first elected in nearly 30 years — would most likely have been completely run by Islamist candidates but for a boycott by the widely popular Shiite organization. It urged voters to stay away to protest constitutional changes that widened the king's powers.
Although the United States Navy fleet for the Persian Gulf region is headquartered in Bahrain, the presence of the base was not even raised as an election issue.
"The government's bad management and poor performance gave the chance to the religious groups to operate and get support," said Sawsan Shair, a columnist for the daily Al Ayam in Bahrain. "Their members have been operating for almost 10 years — building clinics, sponsoring orphans, distributing aid and food and medicine."
The same is true to an extent in Pakistan, although there hostility toward the American presence in the region, and Gen. Pervez Musharraf's support for Washington's campaign against terrorism, were open campaign issues for the religiously oriented parties.
"Issues of identity and Islamic pride are there, and the war on terrorism was a contributing factor," said Rasul Bakhsh Rais, a professor of political science and international relations at the Lahore University of Management Science. But he and others asserted that it was not the main factor.
"There is a deep sense of betrayal among all Muslim people that their elites, their governments, their institutions have all failed them," Mr. Rais said. "People have moved away from the mainstream parties hoping that the religious political parties will provide them with a better alternative."
In Morocco, the most ardent Islamist groups are banned, so those candidates running were allied with the government and unlikely to attack it outright for any links to the West. But they did manage to get the message across in a subtle way by talking about the need to preserve Islamic identity and protect the Muslim world.
That issue seemed to play little role in Turkey, where the overwhelming sentiment among voters was an ardent desire to throw out of office anyone associated with the country's collapsing economy.
The Youth Party, for example, which actually ran something of an anti-American, anti-International Monetary Fund platform, failed to make the threshold of 10 percent of the vote needed to get into Parliament.
The victorious party in Turkey, led by men who recast themselves from Islamists to social conservatives, has taken moderate foreign policy positions. It favors continuing membership in NATO and joining the European Union.
Those would be anathema to more radical religiously oriented groups in the region, especially the Muslim Brotherhood, the root stock of all such groups in the Arab world.
"They are isolationist, parochial," said Mr. Said. "Their point of view is that we have to keep in mind that we are in permanent conflict since the time of the Crusades until now."