This chapter deals with treaties of commerce. As one would expect, Smith wants as few restrictions on trade as possible, and makes a good case.
Page 410: “A direct foreign trade of consumption is always more advantageous than a round-about one; and to bring the same value of foreign goods to the home market, requires a much smaller capital in the one way than in the other.” This brings up again the whole issue of whether transportation adds value, or whether, on the contrary, a portion of the surplus value must be used for transportation. It makes a difference because, in the latter case, transportation reduces profit. Smith is somewhat contradictory on the issue. It may be that it is different in different cases: If I must pay to transport my corn twenty miles to market, whereas another farmer need only transport his two miles to the same market, I cannot charge more for my corn simply because it went further, hence the transportation reduces my profit. Contrariwise, goods shipped from Japan to US markets must always have a certain markup compared to the price of the same item in Japan. Interesting question.