"White evangelicals represent only around 17% of the US adult population, but comprise around 26% of voters. They vote overwhelmingly Republican (an estimated 81% in 2016), making them the party’s single most important voting bloc. That gives them powerful influence on Republican policy, and in particular on foreign policy when Republicans control the White House and Senate (with its treaty-ratifying powers). Fully 99% of Republican congressmen are Christian, of whom around 70% are Protestant, including a significant though unknown proportion of evangelicals."