In chapter 2 of The Undocumented Americans, Karla Cornejo Villavicencio draws attention to the number of undocumented immigrants who were employed at short notice and for short periods of time to clean up the toxic debris in the wake of the 9/11 terror attacks. Many of these workers now suffer from respiratory diseases, cancer, PTSD, and a range of other ailments, for which they have no healthcare coverage.

The cleanup efforts after 9/11 were handled by companies owned and managed by wealthy American citizens—companies that received large sums of taxpayers' money. These companies then subcontracted the work to smaller companies, often run by American citizens of Latin American descent. The subcontractors employed undocumented immigrants to do the work, and supplied them with inadequate protective equipment, leading many of them to suffer serious illness and death. Villavicencio believes that these undocumented workers were the second, invisible group of victims of the 9/11 attacks.

The pattern Villavicencio reveals after the 9/11 attacks has been repeated in the wake of many other disasters, to the extent that it is now a normalized system of exploitation. Apart from the fact that they need the income, undocumented Americans are often eager to help in such situations and take pride in having done so. Their eagerness is matched only by that of the contractors and subcontractors to exploit them.