As Russia hunkers down for "decades" of U.S. sanctions, the chill in geopolitics is threatening to turn into a deep freeze for an economy retooling after the crash in oil prices.

By reluctantly codifying the penalties into law, U.S. President Donald Trump is ensuring that Russia's future may look much like its past as a petrostate. It also marks a shift to a "new normal" that's all the scarier for being impossible to undo any time soon, according to Vladimir Miklashevsky, a senior economist at Danske Bank A/S.

Desperate to snap out of an investment torpor after its longest recession this century, the economy of the world's biggest energy exporter can't afford to remain walled off from foreign capital and technology. Russia was rated 111th among 138 nations in foreign direct investment and technological transfer by the World Economic Forum's Global Competitiveness Report.