<P> While the specifics of the security program are restricted, the multi-layered program effectively eliminates the anonymous shipment of all documents, parcels, counter-to - counter packages and freight on both passenger and cargo - only flights originating within the U.S. Such anonymous shipments were frequent in the years prior to 2001 and led to growing concern in Congress and amongst the general public about the overall security of air travel . </P> <P> In the post-September 11th era, shippers who have been properly vetted with the TSA by an air carrier or freight forwarder are considered a Known Shipper with the TSA . Such shippers may tender their freight for shipment on both passenger and cargo - only aircraft, with some restrictions . Available alternatives for Unknown Shippers to ship via air are now very limited . Collectively, this program is known within the industry as the Known Shipper Program . </P>

Why was congress dissatisfied with the known shipper program