The Department of Homeland Security says it can figure out if you are a terrorist by knowing, among other things, how big your apartment is. The department plans to put that belief into practice this summer under the rubric of the Computer Assisted Passenger Pre-Screening System (CAPPS) II, ensuring that a smorgasbord of information about you and me is available over the Internet for those who know how to look.The basic idea behind CAPPS II is that airline passengers will be asked to provide their full name, addresses, phone number and date of birth and don't be surprised if your underwear size is next. This information will be sent to a commercial database company, such as Acxiom, when travelers try to check in. The company attempts to confirm the traveler's identity using information in its database. Information from the commercial database and from federal databases then will be used to fit the traveler into one of three groups, such as green, yellow and red tags.Travelers who register green would be subject to normal screening and those who come up yellow would get closer inspection. Those who come up red would be barred from getting on the plane.You better hope that you have not been the victim of identity theft, where the thief does something that sets off the red paint gun. You could suddenly be stranded in Newark involved in a very long conversation with some people who are trained to doubt your honesty.Quite a few organizations have come out against this plan and not just the ACLU. Former Republican Congressman Bob Barr, hardly a liberal firebrand, has expressed severe concerns about the potential for violating travelers' civil rights. In addition, the Congressional General Accounting Office says that the system was nowhere near ready for prime time. But this column is not about my dislike for this kind of computerized Big Brother environment. It is about the information on you that is already laid out for harvesting on the Internet by companies such as Acxiom.Fortune has what can be best described as\u00a0a horror story about Acxiom\u00a0in its Feb. 23 issue. Acxiom admits that at least twice hackers have broken into its systems and absconded with records about millions of Americans. The company is an attractive target because it has more than 20 billion records about our activities and environments. Fortune says Acxiom is getting serious about security, but descriptions of what the company is doing do not impress me.Acxiom and other such companies will be empowered to collect even more information about you by the money and authority of the government. It would be ironic if the collapse of the U.S. economy came because the Russian mafia (an example in the Fortune story) broke into Acxiom and used the information to destroy the credit ratings of almost all Americans. Because of the negative information, CAPPS II would not let you fly, even if your credit cards worked.Disclaimer: Harvard's development office would be quite disappointed if the credit rating of potential donors were to be hurt, but I did not ask them about this topic.