The storming of the US Capitol building in January 2021 was a presidential attempt at a self-coup. To make the case, this article reviews elements of the Capitol assault and the events leading up to it, in light of the key conceptual components of a self-coup, and how those compare to attributes of other kinds of attacks on governments. The Trump self-coup will then be compared and contrasted empirically to other self-coups perpetrated by leaders. It is found that what separates successful self-coups from those that fail is whether the military backs the undertaking. Thus, a section is included on US military behaviour in response to Trump's attempts to gain military adherence for his political actions.