This is an area with some experiments actually. Peter Sinegr seems to be involved in a lot of them. He's a famous(ish) utilitarian. Considered pretty extreme. Actually, you can almost use his moral prescriptions as a what happens when you take your above reasoning to the extreme.

Anyway, most people are instinctive deontologists. From the above link:

"the minority of subjects who did consider that it would be right to push the stranger off the footbridge {Right from a utilitarian/net-good perspective} took longer to reach their judgment, and had more activity in the parts of their brains associated with cognitive activity, than those who said that it would be wrong to push the stranger off the footbridge{Right from a deontological perspecitve}"

You seem to be a good example. Instinctively/emotionally a deontologist, rationally a utilitarian. A torn man. (;

I bet everyone is that way instinctively, just some of us think enough to overcome it, for better or for worse.

Most of us are remarkably similar regardless of race, religion, nationality, education etc. are like that.

I think that those who go with a utilitarian approach think harder about the decision, but that might be just because it makes the decision harder. You need to work out consequences. It's a stretch to say it makes it smarter.

But when you get right down to the root of your stack of 'whys,' you generally hit a principle at some stage. When your trying to rationalise morals, that is. Even Bentham the old time 'extremist' utilitarian had 'the principle of equal consideration.'

Your Constitution & other fundamental documents that you sited earlier are essentially principals (held to be self evident, no?). If you are going to try & rationalise your ethics, most strategies can be deciding on what level to define you principles, define them somehow then apply. Most people instinctively do it at the same sort of level as the law. Some mostly pretty bookish characters go to a slightly higher level.

In that respect, the US founding documents (which I am always surprised to hear quoted & treated in the way that they are) conform to that. Confucius as an example goes to a slightly lower level.