This article considers the development of the Tea Party movement, the character of its thinking and the nature of the interests and constituencies to which it is tied. The article suggests that despite the importance of ideas and interests, and the process of interaction between them, the movement has also been shaped and energised by institutional arrangements. In particular, it argues that there are significant numbers of independent or ‘detached’ conservatives and that the institutional architecture draws them towards political engagement but at the same time imposes constraints. The political friction that this creates has contributed to the anger that has characterised the movement. While the Tea Party movement may, as such, have only an ephemeral existence, independent conservatives are likely to remain a significant and potent constituency and will, within the institutional structures that define the American political process, give rise to other movements and protests.