"Not everyone was happy with [Captain America]. This may surprise some people, but before America..."

“Not everyone was happy with [Captain America]. This may surprise some people, but before America entered World War II there was actually a strong pro-Nazi sentiment in the United States. So much so that Simon and Kirby [Cap’s creators] received death threats and mail disparaging them in their creation, not helped by the fact that the two were also Jewish.
In fact, a pro-Nazi group called ‘The German-American Bund’ once marched in front of Timely’s offices [one of Marvel Comics predecessors]...