Thousands of foreign students and scholars have been denied or delayed entrance into the US due to stringent visa requirements enacted after September 11, which bar scientific visitors who might hand over strategic knowledge and technologies to US enemies, even though many have no connection to sensitive technologies.

The United States is basing these new procedures is a government technology watch list that identifies scientific fields with potential military importance.  Anyone studying those areas can be screened for months before being allowed to enter the country, even if they have previously studied or worked in the US for years.

The list includes research areas with clear military significance, such as bioweapons, navigation and laser technology and also includes whole fields of science that have both peaceful and military uses.  These areas include all of microbiology, much of chemistry and physics, and areas such as urban planning, landscape architecture, housing and civil engineering.

The group of scientists delayed or denied includes an environmental engineering student from Mexico, Russian epidemiologists, an Egyptian AIDS specialist, Israeli and Chinese cancer researchers and an Iranian earthquake-safety engineer.  Top Russian scientists collaborating with US colleagues on counter terrorism and arms have also been denied.

The screening process is known as “Visas Mantis.”  Relying on the technology alert list, Mantis requires anyone working in a sensitive field to undergo detailed consular interviews and intensive security checks when applying for a visa.  Some face double jeopardy checked under both Mantis and “Visas Condor,” which flags a range of possible security risks, including applicants from a handful of nations considered sponsors of terrorism.

In the past, most foreign students and scholars could routinely return to the US after visits home or trips to scientific meetings abroad and could get a new visa at a local US consulate in a matter of hours.  Now, if they leave the country, they may have to return to their home countries to obtain a new visa and receive the same intense scrutiny as newcomers.