Roskill on revising sea-power history

Roskill's 1962 Strategy of Sea Power develops an argument from his 1961 Cambridge lectures about how maritime strategy should use history. Its foreword credits Mahan, Corbett, and Richmond while reserving the right to correct their facts and challenge their interpretations. Earlier theorists remain useful because understanding their arguments helps readers follow the writers who build on them. Technological change requires historical principles to be reconsidered, but it does not prove those principles obsolete. Access to evidence also limits revision: in 1961, trustees and literary executors still withheld important Jutland material, including some of Jellicoe's papers and a surviving copy of Captain Harper's Jutland record. Other privately supplied letters and papers helped Roskill investigate the same period. He found Second World War strategy easier to study because he could use the private papers of Charles Forbes and Cunningham. Historical conclusions therefore depend partly on which records their authors were allowed to examine.