Andrey Kostin, chairman of Russia’s state-owned bank VTB and a Vladimir Putin ally, was in the news twice this month. On April 4 The Wall Street Journal published a letter to the editor from Mr. Kostin. He vented in the letter about my March 26 column detailing his vendetta against fellow Russian Igor Bitkov in Guatemala. He claimed the column “perpetuates an inaccurate portrayal of Russia’s banking industry and its state banks.” The next day the U.S. Treasury imposed sanctions on Mr. Kostin and six other Russian oligarchs.

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