A new forum for the U.S. and European Union to settle differences on trade and technology policy has taken on added significance following Russia’s invasion of Ukraine, with supporters positioning it as a model for broader cooperation among free-market democracies. The U.S.-EU Trade and Technology Council had its first meeting in Pittsburgh last fall, which participants said helped forge ties that proved critical when the two economies joined forces to impose sanctions on Russia following its Feb. 24 assault on Ukraine.