https://apnews.com/article/trump-prayer-gathering-conservative-christians-nationalism-c677a4c43070e9da261f4ec5ebcf62a4

https://www.whitehouse.gov/freedom250/america-prays/

The gathering has been organised by the White House as part of a programme of celebrations for America's 250th birthday and, in a video message inviting Americans to attend, Hegseth said it was an opportunity to "rededicate this republic to God and country".

Muscular Christian nationalism has enjoyed a prominent platform since Trump's return to power, and evangelicals form a core element of the president's support base.

I thought America was a secular state?
A secular state is an idea pertaining to secularity, whereby a state is or purports to be officially neutral in matters of religion, supporting neither religion nor irreligion.[1] A secular state claims to treat all its citizens equally regardless of religion, and claims to avoid preferential treatment for a citizen based on their religious beliefs, affiliation or lack of either over those with other profiles.