LONDON — In the five weeks since Russia invaded Ukraine, the United States, the European Union and their allies began an economic counteroffensive that has cut off Russia’s access to hundreds of billions of dollars of its own money and halted a large chunk of its international commerce. More than 1,000 companies, organizations and individuals, including members of President Vladimir V. Putin’s inner circle, have been sanctioned and relegated to a financial limbo.But Mr. Putin reminded the world this past week that he has economic weapons of his own that he could use to inflict some pain or fend off attacks.Through a series of aggressive measures taken by the Russian government and its central bank, the ruble, which had lost nearly half of i …
