yes, it is true that Asia/Pacific is not your issue but there are a number of people who are hellbent in trying to argue that DL is dying in Tokyo. and they'd love to make you believe that DL is losing money.
Japan is a shrinking market but DL is maintaining its share and is making money.
specific to your question about Russia, the majority of DL's traffic between Russia and the US is Russia originating which probably means it is Ruble denominated. However, DL has long carried a lot of immigrant traffic which is largely paid for from the west but is one way out of Russia.
Thus, it is possible that DL is suffering currency losses but whether DL's decision to reduced capacity is due to reduced demand at any price or because the traffic is heavily Ruble denominated, DL is reducing capacity.
and that is precisely the type of strategy that an airline has to make when currencies swing wildly and there are no hedges in place.
The reason why DL did reduce as much Tokyo capacity initially is because DL had hedges that were covering several hundred million dollars per year in hedge losses.
DL does not have currency hedges against the Ruble or has not disclosed them just like AA does not have hedges against currencies in Argentina, Brazil, or Venezuela.
When there are no currency hedges in place, the full impact of the currency changes goes directly to the revenue bottom line, just as it does with fuel on the cost side.
DL and UA have far less of their revenue at risk due to currency fluctuations but they have hedge losses which are losing money right now while AA has more revenue at risk due to currency swings but little fuel exposure right now - although DL did have gains from fuel in the past and when fuel starts going up carriers that hedge - which will include DL - will benefit from those hedges wihle AA will eat the full cost of the increases.