This morning the TSA, in conjunction with local police forces, will "carry out a show of force" at 150 rail stations on the East Coast. This is an effort to prepare for any potential terrorist threats.
One thing this signals is the beginning of the end of one of rail's greatest conveniences over air travel. Transportation planners have steadily maintained that security measures now in place at airports will eventually reach rail travel, and they have been steadily ignored by rail proponents, who have argued that rail is a more convenient mode of travel because you can just walk up, buy a ticket and get on board. Once this advantage is lost it will be interesting to see how ridership responds. The additional security will certainly diminish the viability of any new intercity rail projects.