Professional athletes who take a knee or lock arms during the national anthem have been clear about their rationale. Eric Reid of the San Francisco 49ers wrote that he kneels because of "the incredible number of unarmed black people being killed by the police," and Oakland Athletics catcher Bruce Maxwell explained it's "not to disrespect" the military, country, or Constitution.

But that message hasn't always gotten through — especially since President Trump has gotten involved. As a result, as a new FiveThirtyEight analysis details, polls gauging public support for the protests have produced varied results that depend significantly on whether and how the purpose of the players' action is framed.

Surveys that don't specify the athletes' motive "either rely on the respondents' prior understanding of the situation or simply measure people's appetite for protests that use the nation's symbols." In this patriotism-focused framing, polls typically find about half of Americans oppose the protests and 35 to 45 percent approve.

When the protests are cast as a free speech issue, however, the picture changes. While it's still true that a majority would prefer the athletes to stand, only about one third of Americans say they should suffer consequences like firing if they don't.

Linking the protests to racial inequality produces different results, too, tending to bring approval and disapproval rates closer to parity, though still leaning toward disapproval. And regardless of framing, there are consistent racial disparities in poll responses: Black Americans are always far more likely than white Americans to find the protests appropriate. Bonnie Kristian