No analysis of the Donald Trump phenomenon and American neo-nationalism is satisfactory without examining the impact of both the Christian Right and the secular nationalist right, both in the USA and abroad. This book analyses the political impact of both strands in relation to America’s culture wars at home and the clash of civilisations in the USA’s foreign policy. Each strand — religious and secular — has had different issues to pursue during the Trump presidency; religious liberty and associated issues, on the one hand, and 'America's place in the world', on the other. This book demonstrates how both strands overlap and draw on each other's concerns to exhibit a pronounced, multifaceted neo-nationalism which was ideologically important for the Trump presidency. The author emphasises that the Trump phenomenon has been building for decades, and the Trump presidency has used significant political, social, economic, and cultural disquiet, and the post-2008 economic crisis and associated global turmoil, to fashion and progress policies which appeal strongly to both the Christian Right and many secular nationalists. This book will be of interest to students, researchers, and policy-makers interested in American politics, American political history, religion and politics in America, and religion and IR with a focus on the USA.