A) Kusari is protectionist and authorian, and the overwhelming import of diamonds are overheating the market, dumping prices, and creating a trade deficit. What do the protectionist do? Control the trade.
B) That niobium is also used in Kusari shipyards. You know, war going on? To allow unrestricted export to Rheinland drives prices up, and harms the war effort. (It also harms Samura. Samura has a lot of political power.)
That would be the in-rp reasons for trade regulations.
C) The regulations as envisioned are not set up to stop trade alltogether, just to limit the profitability of the two-way run
/w
John Johnson - Master of Synth.Foods-Convoy|049
Hans Adler - Synth Foods escort wing