In Miami, the crowd was standing and cheering Friday as President Trump smiled broadly after pledging to reverse key provisions of the Obama administration’s historic Cuba opening. A world away, in Portland, Maine, Ben Rhodes could not contain his frustration. “The few people in Miami enabling Trump in carrying out this charade should be embarrassed/held accountable,” Rhodes wrote on Twitter. “He could care less about Cubans.” It was the first of four tweets Rhodes, a foreign policy aide to former president Barack Obama, fired off attacking Trump as the president was speaking. Rhodes was in Maine to attend the wedding...