By ANDREA ELLIOTT In the wake of 9/11, Muslim immigrants from Pakistan, Egypt and other countries have found themselves living in a newly suspicious America. Many of their businesses and mosques have been closely monitored by federal agents, thousands of men have been deported and some have simply been swept away – “rendered” in the language of the C.I.A. – to be interrogated or jailed overseas. But Muslim immigrants are not alone in experiencing the change. It is now touching the lives of some American converts: men and women raised in this country, whose only tie to the Middle East or Southeast Asia is one of faith. Khalid Hakim, born Charles Karolik in Milwaukee, could not renew the document required to work as a merchant mariner because he refused to remove his kufi, a round knitted cap, for an identity photograph last year. Yet for nearly three decades Mr. Hakim’s cap had posed no problem with the same New York City office of the Coast Guard. In Brooklyn, Dierdre Small and Stephanie Lewis drove New York City Transit buses for years wearing their hijabs, or head scarves, with no protest from supervisors. After 9/11 the women were ordered to remove the religious garments. They refused, and were transferred, along with two other Muslim converts, out of the public eye – to jobs vacuuming, cleaning and parking buses, said the women, who are suing the Metropolitan Transportation Authority and New York City Transit. “I’m a U.S. citizen and I’m supposed to be protected,” Ms. Lewis, 55, said with tears in her eyes. “On 9/11 I was scheduled to take policemen to that site. I felt compassion like everyone else. And now you’re singling me out because I’m a Muslim?” New York City Transit officials said they would not comment because the case is in litigation. Regardless of how their cases play out legally, Mr. Hakim, Ms. Lewis and other converts have come to view America after 9/11 through a singular lens. An estimated 25 percent of American Muslims are converts. Some came of age as Americans first and discovered Islam as adults.