Chicago ? The questions since the Sept. 11 terrorist attacks have ranged from benign to offensive, Kareem Irfan said.

He has been asked frequently whether Islam condones suicide bombing and once why Muslim women are “expected to be your slaves?”

An attorney and Muslim community leader in the Chicago area, Irfan said he easily could respond to the onslaught of inquiries from his neighbors and co-workers, but many more American Muslims could not.

To help them, the largest U.S. Muslim convention of the year is offering what amounts to a crash course in basic Islamic teachings so the thousands of attendees can return home more confident about defending their faith.

Panel discussions at the event, which runs through Monday, include dispelling myths about the Prophet Muhammad, interpreting Quranic verses and a session entitled “Answering Difficult & Frequently Asked Questions about Islam from American Audiences.”

“People have been under a lot of pressure. They need a certain amount of spiritual strength to put up with the day-to-day barrage about Islam,” said Ingrid Mattson, a vice president of the Islamic Society of North America, which has organized the convention.

Mattson, a professor at Hartford Seminary in Connecticut, said the sessions also aimed to convince Muslims “to come out of their shells and that it’s OK to be a Muslim in America.”

Muslims began settling in the United States in large numbers in the 1960s, when the federal government loosened some restrictions on immigration. Estimates of the number of American Muslims today vary dramatically from 2 million to 6 million.

But until the 2001 suicide hijackings, many Americans were not aware of the significant Muslim population in this country. Since then, non-Muslims have grown more curious — and more openly critical — of the religion, Irfan said.

Alpasian Yaman, left, of Parsippany, N.J., participates in the afternoon prayer as his son Hamza sleeps during the annual meeting of the Islamic Society of North America. The convention continues through Monday in Chicago.