We see Mr Darcy (Colin Firth) or at least a stuntman, diving into the lake. How to respond to Russian warplanes entering Estonia's air space? The obvious way is to zap 'em which might be very satisfying but carries risks. ” If the Kremlin then ordered its warplanes to withdraw it would be seen as weakness. But if it told them to continue the incursion, mighty Russia would appear to be doing it with little Estonia's blessing, again looking weak.