The National Security Archive at The George Washington University is well-regarded for their Electronic Briefing Book series, and this particular entry edited by William Burr is yet another fine addition. This particular work looks at the question of "how much is enough" as regards the necessary number of US nuclear submarines in the early 1960s. It was a subject of the utmost concern to military leaders, particularly the Chief of Naval Operations, Admiral Arleigh Burke. Burke's primary argument was that a small force of mainly nuclear-launching Polaris submarines was enough for effective deterrence. This engaging collection of formerly classified documents and other materials takes a close look at how the US Navy tried to take responsibility for this situation by effectively supporting a minimum deterrent force that could destroy a targeted list of significant urban-industrial and command centers in the Soviet Union. All told, this book contains nineteen documents, including the record of Burke's conversation with the Secretary of the Navy and his own "Dope" newsletter to top Navy commanders where he noted that preemptive nuclear strategies were "dangerous for any nation".