"Tying one's hands" can be a way to commit credibly to a certain course of action. In the 1960s film Dr. Strangelove, the Soviet Union deployed a doomsday device that could destroy the world and would be automatically triggered if the United States attacked. Explain how such a device could serve as a credible threat to deter a U.S. attack. In the movie, the Soviet Union did not inform the United States that the device had been deployed. Why was this a really bad strategy?