This is where the "War on Terror" treads on the Bill of Rights. I, personally, don't oppose high security on all domestic and international flights. However, all travelers should be screened equally. We, in the US, have become very complacent and lazy. We want the authorities to have a firm grip on all matters of security, but we want NO INCONVENIENCE in the process and do it without spending any additional money. It's a shame we don't travel outside our borders more often. We would understand insecurity, hunger, poverty and corrupted government with a new found clarity and also why we're considered to be arrogant and rude.
Yes we can be too paranoid. If we prevent people going about there normal lives without too much interference then the terrorists have already achieved their goals. And if someone that is quite clearly sick is detained or arrested then racism could be an issue. Would this man have been detained if he was white? In America probably not.
We can never be too paranoid after 911!!!! Race isn't the issue, protection and safety are. Terrorism has no race.