The notion that the media’s principal role regarding public opinion is reinforcement of pre-existing attitudes – and that this idea is relative inconsequential politically – is pervasive, across many political and social science sub-disciplines, and in non-academic commentary. This article comprehensively challenges the evidential and theoretical underpinnings of this thesis, drawing on a wealth of contemporary survey data and media coverage research, across a range of issues, including climate change, Brexit, immigration, the economy and benefit fraud. It also argues that ‘reinforcement’ is an important and consequential power, and that the processes involved have significant implications for public misperception of salient political issues. It makes the case that the media create attitudinal uncertainty, and can have pervasive but subtle influences on political attitudes, particularly when there are persistent patterns of coverage across a range of media. But also that in contexts like particularly close political contests, such influences can be decidedly consequential.