Engineers still do wear iron rings in Canada. The organization that does this has chapters in the US, but it isn’t as pervasive as it is in Canada.
I remember as an undergrad I was considering aerospace engineering as my major. I was told that they don’t give partial credit as a rule on problem sets or tests because when you’re engineering a plane, there is no partial credit. You either get it right, or people die.
With programming, we have a slightly different problem. It isn’t just a question of faulty coding causing deaths, although that can certainly happen too. It’s a matter of recognizing a request that would be a breach of ethics, and having the courage to refuse the request. Even worse, it is knowing that if you refuse, they’ll just find someone else to do it — even if they have to go outside their company to a freelancer. In the absence of a safe method for whistle blowing, that thing you refuse will end up happening.