A bidirectional gas discharge tube (GDT) includes a discharge chamber, first and second cathodes, a gas disposed within the discharge chamber, and a control grid. The first and second cathodes are disposed within the discharge chamber and include first and second faces, respectively. The first face and the second face are plane-parallel. The gas is configured to insulate the first cathode from the second cathode. The control grid is disposed between the first and second cathodes within the discharge chamber. The control grid is configured to generate an electric field to initiate establishment of a conductive plasma between the first and second cathodes to close a conduction path extending between the first and second cathodes.