This is not to say penetration of espionage services has not caused serious damage to the other side, but rarely has it been decisive across the board.

It is only at the highest level, where this data is collated and integrated into national policy, is the possibility of a single mole potentially devastating. In fact, it is often complained that very good intelligence exists of enemy action which somehow never filters up to those in charge of integrating it all into a view of enemy capability and intentions which can guide policy.

Usually, when the dust settles, it is determined we really knew what the bad guys were up to all along, we just never connected the dots and put it all together in time. And of course, efforts to reorganize to counteract this tendency by increasing access to material to lower level operatives just make you more vulnerable to lower level moles. Finding the right balance is a difficult management problem.

And of course, the biggest problem is misinterpreting your enemy’s intentions; for example, when your ideological propensities mislead you to mistake an enemy defensive weapons technology for a offensive one, and you wind up wasting resources defending against a threat that doesn’t exist, neglecting those that do, and transmitting to the enemy the idea that you are the villain preparing for a sneak attack. It is amazing how actions can be misinterpreted, sometimes with tragic results, because one side thinks it knows what the other is thinking.

Those years when Walker, Ames and Hanssen were operating It was like playing Battleship with the Russians while they were looking at both sides of the board without the US knowing it. That is a huge loss, comparable in football to the opposing teams having your playbook and knowing the calls. All the calls. That doesn’t compare with someone on the sidelines saying just before a play that it will be a run.

Whatever. That game does describe the position the US was in.

Real battleships is deadly serious. The fate of nations is decided, and men die horrible deaths. But the game is for losers.