After sixteen months of Western sanctions against Russia the picture of their efficiency remains ambivalent. The sanctions on oil exports have proven effective in achieving the objectives: reducing Russian budget revenues while avoiding destabilisation of the world market. However, the sales of Russian oil have increased and the Russian state budget still earns money.

For Russia challenging the US self-proclaimed 'sphere of influence' in Venezuela is a very cheap gamble, says our security expert Mark Galeotti. An airplane with armed men, a couple of threathening statements, and flexing of some muscles is all it costs. Rosneft investments in the Venezuelan oil industry could suffer. But that is probably an affordable loss and shrewd political calculation.