Reporting from Washington — For decades, Republican doctrine has viewed Russia as a power to mistrust. But in Donald Trump’s GOP, Moscow’s sins seem to matter less. The platform written at the GOP convention in Cleveland this week eliminated references to arming Ukraine in its fight with Russia, which seized the Crimean Peninsula in 2014 and has supported separatists in eastern Ukraine.Those represent sharp departures from U.S. policy and recent GOP positions and sparked immediate concerns that Trump would abandon treaty commitments to allies. Ohio Gov. John Kasich, who is not attending the convention in his home state, was among...