I have first-hand experience dealing with Michael Chertoff. You may not know the name, but he's been a SCOTUS clerk, federal prosecutor, Assistant U.S. Attorney General, NSA Director, and Secretary of Homeland Security.
He was also chairman of BAE systems, The Chertoff Group, and other defense-oriented businesses. BAE is D.C.'s 8th largest contractor.
Chertoff was instrumental in mandating the FAA's adoption of body scanners for security in his capacity as a public official.
As a private citizen, The Chertoff Group represents lobbying efforts for security product companies and manufacturers.
Airports may or may not need body scanners. I think that the general HN audience is more familiar with Schneier's work enough to know of the 'security theater' that they represent, but even allowing for the possibility that they actually do some good, it seems absolutely absurd to me that the director of the NSA or the Secretary of Homeland Security has the power to mandate their purchase and installation with one hand, while selling them to the government with the other.
Assuredly this is neither the most or least egregious example of federal corruption, but I think it's the most illustrative. To me, the federal government has only the powers enumerated in the constitution. Mandating security devices isn't one of those powers, but the federal government has claimed it in its purview.
I don't necessarily have a problem with the federal government trying to keep us safe, if that's what they're doing, and I certainly don't mean to besmirch Chertoff as the archetype of corruption -- he may very well have the best possible intent... but at the same time, it would be silly of me, as president, to insist that only the software company I owned could possibly manufacture secure-enough solutions for the government and mandate their usage as vendor.