当政治转向改变行为而非信念：新冠危机期间特朗普在口罩问题上的立场反转

Political leaders play a potentially important role shaping behaviors and beliefs during crises. In the pandemic, a number of high-status politicians, notably leaders of populist parties, were seen to diminish compliance with institutional recommendations by casting doubt on COVID guidelines. But what happens when such leaders change position and endorse previously discouraged behaviors? Using longitudinal data from the Understanding Coronavirus in America panel with fixed-effects modeling, this article examines how Trump’s unexpected endorsement of facemasks in July 2020 affected individuals’ likelihood of wearing a facemask and belief in masks’ efficacy. I find that Trump’s pivot lifted Republicans’ use of facemasks, closing 40 percent of the preexisting gap with Democrats and with stronger effects among individuals who were more exposed to the early-summer spike in COVID cases. Additionally, I provide evidence for the unique significance of this moment in the history of the pandemic, showing that at almost no other time did partisan behaviors converge as sharply. However, in contrast to expectations from most dominant theoretical models of behavioral change, especially the health belief model, no corresponding shift in beliefs about facemasks can be detected. These results have important theoretical implications for understanding how pivots can shape behaviors during crises, the validity of existing models in public health, pandemic populism’s causes, and directions of future research.