YOu can normally have your bag inspected in front of you before it gets eaten by the airline, that way you can lock it with a NON Tsa lock. One word of caution: one of the inspectors showed me how easy it was to open a locked zippered bag and close it again with no sign of entry, if you are really worried use either hard side case or one of the steel mesh bags made for backpacks. Or the best solution: we could vote in a honest and rational congress! Better get the hard side bag till then.