evidence: Walker also made the claim in a column and several earlier tweets, one of which invoked Sanders’ oft-cited Soviet Union honeymoon. President Donald Trump said the same in a Feb. 2, 2020, interview before the Super Bowl. And former New York Mayor Mike Bloomberg invoked communism while criticizing Sanders’ monetary policy at the Feb. 19, 2020, Democratic primary debate. [...] When we asked Walker for evidence of his claim, a spokesman cited a laundry list of past actions, including Sanders praising leaders of communist governments, visiting the Soviet Union on his honeymoon and traveling to several communist countries. [...] Lowell Barrington, associate professor of political science at Marquette University, said Sanders has made himself "vulnerable" to attacks like Walker’s because he has spoken positively of communist leaders like Cuba’s Fidel Castro. But he echoed others in saying Sanders’ proposals are more in line with the northern European brand of socialism than the authoritarian communist regimes seen in the Soviet Union, Cuba and the People’s Republic of China.