You got to give a little
Contrary to the style of the political purveyors of pabulum on the tube, giving a little here and there is not a sign of weakness. It is a brilliant way to sway the discussion in your favor.

“Give me a for instance, Emil.”

Okay, your friend agrees with you that some of your “concerns” regarding policy B have some merit, but, MY GOD, WE HAVE TO DO SOMETHING.

Agree with them. Say, “You make a good point, BUT…” Acknowledging the merits of opposing viewpoint enhances the discussion in many ways. First and most important, it encourages the other person to listen to you. By agreeing with something they’ve said at the outset, they’ll pay closer attention to everything you have to say after that. After all, you may flatter them again and they wouldn’t want to miss that!

It also creates an environment of respect. You’ve listened carefully to their viewpoint, flattered them by highlighting the points on which you either agree or, at the very least, feel have merit and thus increased the odds that they will return the favor. It shows that you are a reasonable person and we all listen more closely to people we view as reasonable.

What’s the catch?

The only drawback to this technique is it requires you to listen the other side’s point of view more closely than you might normally; the risk being you may see an issue differently than before. But go ahead and risk it. After all, you know you’re “right”…or “left.”