This is a question somebody asked on the Objectivism subreddit. They wrote:

Since there are so few objectivists, most of us likely have friends and relatives who are not objectivist. What do you guys do when one of them makes an irrational remark about political or cultural issues? It's tiring to constantly argue with people and it doesn't make you very fun to be around so I tend to ignore it unless I'm in the mood for an argument.

This question is important – many people have to contend with this problem at family gatherings, eg during the holidays.

Here’s my answer:

Your question is a special case of the more general question ‘How does one lead a rational life in an irrational society?’ For you, specifically, it translates to: ‘How do I lead a rational life among irrational family and friends?’

Ayn Rand addresses the general question, and by extension, your specific case, here.

In short, pronounce judgment in the appropriate amount and when it is rationally appropriate to do so. If your family members and friends can’t be reasoned with, a simple ‘I disagree’ whenever they say something irrational or evil is enough [meaning there’s no need to escalate things into a full-on argument]. Just ignoring the problem generally isn’t a good idea because it helps evil triumph over good.

A couple of side remarks:

You can’t choose your family, but you may ask yourself whether you wish to be friends with people who are irrational, and whether being rational yourself shouldn’t rank higher in your hierarchy of values than being fun to be around. Besides, having rational friends means such considerations won’t be necessary anyway – you will be fun to be around by being rational.

You imply that anyone who isn’t an objectivist is irrational. That doesn’t sound right. Sometimes, people are just mistaken in their views, and whether or not they are rational depends on how they deal with being mistaken.

To give some more detail, Rand’s position in the linked essay is essentially this: “One must never fail to pronounce moral judgment.” As in: moral agnosticism is bad – it corrupts your character and favors irrationality over rationality. You must never allow your values to be attacked and stay silent. Pronounce judgment whenever silence could rationally be mistaken for sanction of evil. For example, if someone jokes about how rich people lost their homes in the Malibu fires, as a family member of mine once joked, you should say that that’s not okay.

Sometimes, pronouncing judgment isn’t reasonably possible – eg if you live under a regime where pronouncing judgment could cost you your life – but even then you should still form some sort of judgment mentally and either keep it to yourself or say it out loud only when it is safe to do so.

I’m not sure why OP wants to be friends with irrational people. Also, he may investigate whether he himself is really as rational as he thinks he is. He can’t always have been an objectivist – nobody is born that way – yet he presumably wouldn’t consider his past self irrational just because of that.

Whenever people claim, implicitly or explicitly, that they’re fully rational, I get a little queasy. Reminds me of people who advertise that they never lie; those are often the worst liars.