It was a Mexican stand off, the Algerines fired first and lost. The Dey was gambling and was outfaced by Exmouth. At the time, European powers applied a lower level of respect for the rules of war when treating with non-European powers than they did amongst themselves. Exmouth's actions pale into insignificance compared to Napoleon's execution, in cold-blood, of several thousands of Turco-Arab prisoners of war in Palestine. Napoleon would not have done the same to European prisoners of war (possibly excepting Cossacks).