President Donald Trump is holding back on sweeping new economic penalties Congress handed him to squeeze Russia.He is betting that keeping those sanctions in reserve will help bring Vladimir Putin to the negotiating table, a strategy drawing criticism from Republican allies amid questions about whether Moscow believes he will ever use them.Over roughly a week, the administration waived most of the new Russia sanctions and tariffs enacted last month while separately easing restrictions on Russian diesel exports, moves one foreign policy expert described as Trump's most significant effort yet to...