The Byzantines pumped it at the enemy through huge tubes or hurled it at them from portable siphons almost like modern flame throwers. Even water would not put it out. So it was fairly easy to destroy an enemy fleet. Greek fire frightened the enemy even more. But the Byzantines did not rely only on the army or the navy to win their battles for them. Helping them in every way was the Byzantine diplomatic service. For just as the Byzantines did not ever fight a battle if they could find some other way of winning it, so too they didn’t even begin a war unless they had to. Why fight if they could persuade an enemy to become their friend and ally? Why fight, and risk their own safety, if they could talk someone else into fighting for them? To the Byzantines, this made sense. It was up to their diplomatic service to do this, and the reason it was able to do so very often was because here too the Byzantines knew just what they were doing. Under the Logothete of the Dromos, they had an almost modern intelligence system taken care of by a special department whose one job was to collect information about foreign nations. How can such and such a country help the Byzantines and how can it hurt them? How can it best be won over by the Byzantines—by force, by honors and favors, or by gifts? If the last, by what kind of gifts? Has it any enemies, and if so, who are they? What were its origins? What is its history? What is its climate and its geographical position? Has it usually been a friend or an enemy of the Byzantines? Trace this back to the day when it first appeared on the scene! With this information—the questions had been carefully worked out by the emperor Constantine Born-in-the-Purple in a book called _How To Run the Empire_—the Byzantines could select the right method for the nation they were interested in and then go to work on it. If the ruler or his ambassador was easily dazzled, they could impress him with court ceremony and with purple shoes and robes, and they might even give out a title or two such as patrician or _archon_. They might even take some northern duke or count and promote him to be prince or king provided he swore allegiance to them. If he was greedy and avaricious—and, said Constantine, “the tribes of the north demand everything and hanker after everything”—they could give him cash in hand or even pay an annual tribute.