Clarify please, the Presbyterian Church USA. Personally, I think the PCUSA should just retitle their religion to the Lesbyterian Church to avoid confusion. Bible-believing Presbyterian denominations such as the PCA and the ARP among others are the true heirs to John Calvin, John Knox, Peter Marshall, Matthew Henry and others.
I hate to break it to you, but the PCA is insignificant; ARP utterly so. The entire world body of the ARP could show up to a minor league baseball game and not attract notice in the local press.
Judging the Presbyterian church by the ARP is like judging Catholicism by the Latin-mass crowd.