Russia's mobilization measures and impending annexation referendums in Ukraine will significantly aid Moscow's ability to continue the war into next year, but they are unlikely to greatly reduce Western military support for Ukraine, and will come at the cost of greater international isolation and domestic instability. On Sept. 20, the leaders of the four self-proclaimed pro-Russian occupation authorities in Ukraine's Luhansk, Donetsk, Zaporizhzhia and Kherson regions declared their intention to conduct ''referendums'' on their regions joining the Russian Federation from Sept. 23-27. On the same day, lawmakers in Russia's State Duma approved adjustments to the criminal code stipulating harsher penalties for failing to report for military duty, surrendering or refusing to fight. Then on Sept. 21, Russian President Vladimir Putin said Russia supported the referendums and announced he had signed a decree authorizing a partial mobilization of the Russian armed forces, a measure he said was necessary to ''defend Russia's...