Two of Sun Tzu's five fundamentals of war are "politics" and the "commander". Marco Polo seems to have been intent to give flesh to these concepts through his description of the ruler Kubai Khan and the arrangement of his court. For Tzu's fundamental of "doctrine" Polo seems to give brief word sketches of the religious beliefs of many of the places he visited, (from his European perspective.) With the fundamentals of "weather" and "terrain", Polo seems to combine them into a strong interest in the flows of water that were encountered. It appears that Polo got this interest from several lines from Tzu. Two of which are, "When torrential rain tosses boulders it is because of it momentum"(chapter 5), and "Water can isolate an enemy"(chapter 12). It is worth noting that the first line has a metaphoric connection to war, whereas the second line has a direct application. (Tzu's book The Art of War is not secret any more, being available in bookshops; it is considered one of the classics of world literature and well worth reading for anyone interested in this type of material).
In Polo's book (usually titled Travels), there are sections such as the following: "The lay-out of the city is as follows. On one side is a lake of fresh water, very clear. On the other is a huge river, which entering by many channels, diffuses throughout the city, carries away all its filth and then flows into the lake, from which it flows out toward the ocean. This makes the air very wholesome."(chapter five) And this one: "The Island lies in a sea so turbulent and so deep that ships cannot anchor there or sail away from it, because it sweeps them into a gulf from which they can never escape."(chapter six)
By the time the Knights Templar were declared to be no more they had drained swamps, channeled lagoons and other bodies of water, and also cleared forests and developed salt flats. If, as I contend, Sun Tzu's The Art of War was a powerful influence on them, these projects may have had a hidden purpose for the Knights Templar. That being the removal or lessening of natural barriers between ethnic groups or sovereign states allowing for them to be provoked into war. The objective for the Knights Templar being to profit from war. This was not a lesson from Sun Tzu's book but something this group of knights had fallen into.
Sun Tzu's words on the tactic of deception also seems to have been important to the Knights Templar. It might be that the claim of the Templars that they had discovered the lost ark of the Covernant and that this ancient treasure gave great and mysterious power, was simply a deception related to their practice of warfare.(My main source on the Knights Templar is "The Mystery of the Knights Templar" by Scott Corrales in the book The Conspiracy Reader , compiled by Al Hidell and Joan d'Arc)
When the charges of devil worshiping and criminality were made agaist the Templars, Pope Clemens V dissolved their order (in 1310), after which the grand master and several knights were accused of heresy and burned at the stake. Their possessions in France were confiscated by King Philip IV. But historical parallels (or continuities) suggest that the Knights Templar did not really end with these actions, instead, that they went "underground" and emerged in England with the operational cover of having developed their group out of the trade guide system, with the name that they took being derived from one of the trades, that of the stonemasons. The name that they took being the Free and Accepted Masons. The "Free" part of the name has the meaning of "no longer bonded", a reference to the days of the guilds, where an amount of money had to be paid if an apprentice did not finish his agreed term with a master craftsman. "Accepted", means being a member of the brotherhood but not a mason by trade.
The concept of bonding an apprentice to a master from the old days of the guilds had been given a new meaning. I mentioned this when discussing Captain Bligh in the New South Wales colony. Individuals who were offered "protection" and benefit were "bonded" to the Masons.
The arrangement of the system of "protection" and "bonding" seems to have been informed by the use of Marco Polo's description of the city between the lake and the river as a metaphor. Street criminals of various sorts are "air", or more exactly, air that is impure. The Masons and those bonded to them are "water". The water flows through the city removing the filth, making "the air very wholesome". The filth is washed back into the lake, from which a river flows to the sea. The criminal element infiltrates ordinary society, then proceeds into the international sphere, particularly through war.
The crossed compasses, the symbol of the Masons, also appears to have originated with Marco Polo and Sun Tzu's book. Marco Polo traveled to China from Venice and so would have found maps and a compass (or a pair of them) useful. With the symbol of the Masons, one compass has its points going down, with the connecting joint up. The other compass has the points going up and the joint is down. Together they form a simple pattern. A meaning can be extracted from the pattern. If you begin with the point going down which is on the left and trace up to the connecting joint and down to the other downward point, then trace the part of the other compass that is between those two arms of the first compass, you can extract an "A", except with a crooked cross bar. Then if you trace the lines along the top edges of the symbol considered as a single unit, you get a "W". The "A" and the "W" (in my view) represent The Art Of War, as the title is written in the English language. This then, would link the Masons to the Knights Templar, of medieval times.