It wasn't too long ago where nobody cared that George Romney was a Mormon or that Nixon was a Quaker. William Howard Taft didn't even believe in the divinity of Christ. As we have gotten less religious as a society, the voices of the faithful seem to have gotten louder. Whether that is a good or bad thing depends on where one stands on the issue of religion in public life.
I don’t think its that the religious people have gotten louder. In the 1950’s, people didn’t talk about private matters. Your neighbor didn’t talk about his gay son, or his erectile dysfunction, or about how he might lose his job, or about his religion (unless you went to the same church).
But in the 1970’s we all started “expressing our feelings” and nothing was private anymore. That included religion.
I stopped going to church in 1974 and didn’t go back until just a little more than a year ago. During my 35 years of being non-religious, I met a few pushy Christians, but I met a lot more pushy anti-religious people.
I live in the south, so there are a lot of evangelicals running around. Even they usually make it clear what their beliefs are and then leave you alone if you aren’t interested.
But the loud people are almost always the anti-religious ones. They are the ones that will walk into a break room at work where two people are discussing church and launch into a rant about the “magical sky fairy” and “brainwashed morons” and such.
This makes people with weak faith scared to move towards the church because they know that they’ll be ridiculed for it by some of their friends and co-workers. It also strengthens the faith of those who can withstand it.
The Tafts (William and Robert), the Adamses (John, John Quincy, etc.), and even the founder of the John Birch Society, Robert Henry Winborne Welch Jr., were Unitarians.