In the past, maples were tapped from Virginia to Northern Canada, though currently only a few US states, Ontario, and Quebec produce meaningful amounts. Maple trees grow the world over in abundance, so why does only North America produce syrup? The traditional response is that the conditions for sap production only exist in North America — cold spring nights with warmer days cause the trees to produce sap, which then rises up the trunk as it warms. Because where in the rest of the world is it colder at night than it is during the day? The truth, as you may have guessed, is somewhat more complicated and politically fraught.Along with the decision to reinstate slavery in France’s oversea colonies, the institutionalized plunder of art museums across Europe, the deaths of millions of Europeans during 17 years of war, and the renaming of the mille-feuille (a deliciously ancient dessert), Europe’s failure to crack the secret of maple syrup was Napoleon’s fault.