This AP report mainly focuses on the possibility of AQ conducting attacks in Latin America, but it does mention a few U.S.-specific items:

Governments throughout Mexico and Central America are on alert as evidence grows that al-Qaida members are traveling in the region and looking for recruits to carry out attacks in Latin America - the potential last frontier for international terrorism...

...U.S. officials have long feared al-Qaida could launch an attack from south of the border...

...Mexican and U.S. border officials have been on extra alert, checking foreign passports and arresting any illegal migrants...

In South America, U.S. officials have long suspected Paraguay's border with Brazil and Argentina as an area for Islamic terrorist fund-raising. Much of the focus has fallen on the Muslim community that sprouted during the 1970s, and authorities believe as much as $100 million a year flows out of the region, with large portions diverted to Islamic militants linked to Hezbollah and the Palestinian militant group Hamas...

Concerns increased this summer about whether Mexico was doing enough to screen international visitors after a 48-year-old South African woman arrived in Mexico with a passport that was missing several pages and then waded across the Rio Grande into Texas.

Farida Goolam Mahamed Ahmed was arrested July 19 while trying to board a flight in McAllen, Texas. She pleaded innocent Friday to immigration violations and was under investigation for links to terrorist activities or groups...

"U.S. officials have long feared al-Qaida could launch an attack from south of the border"? So, like, why haven't they tried to, like, you know, prevent as many illegals as possible from coming here? And, "arresting any illegal migrants"? They do arrest about a million a year, but they also let a million a year come here.