When the 9/11 terrorists took control of four aircraft on that fateful morning in 2001, it mattered not what the final destination of each plane was because the terrorists did not intend to land them. Instead, their sole aim was to use these aircraft as crude, but effective, missiles and fly them into four buildings. The bottom line, therefore, is that any aircraft flying over the United States could potentially be used in a similar manner if another suicide terrorist cell were able to gain control of the cockpit. It would be entirely wrong to differentiate between aircraft that are scheduled to land at a US city and those that are merely flying over US territory.

Neither type of flight has to be scheduled to land in America, but merely enter US airspace, to be a potential target for al-Qaeda and its affiliates. In fact, given that the 500+ aircraft that over fly the US daily originate from airports beyond the control of US authorities, terrorists might well conclude that it might be easier to take of control of an aircraft leaving a foreign airport than it would be to attempt to board an aircraft leaving from a US city, not least because, whilst there are obvious security shortcomings at US airports, the screening process is far more vigorous than is the case at some of the foreign airports from which aircraft over flying the United States originate. The level of security on board US carriers is also higher than on several of the foreign airlines over flying the United States that do not normally carry sky marshals or have armed pilots. Given that some of these aircraft are the largest commercial airliners (including Boeing 777 & 747, Airbus A-340 and MD-11) and carry much larger numbers of passengers, such flights might also be of more interest to a terrorist than the typically much smaller aircraft used on domestic routes.