Cards come in three primary flavors. Emotion, Status, Experience.
Examples.
Emotion: Love “You’re not in love, you’ll never understand.”
Status: Race “You’re not black, you’ll never understand.”
Experience: Occupation “You’re not a solider, you’ll never understand.”
This apart from the fact that understanding does not equal agreeing, the X card is any argument point designed to exclude an opponent on grounds other than rationality. For which the only implied defense is metamorphosis of the debater, not the idea.
It is a clever form of the argument from authority or perhaps Ad Hominem. As a good rule of thumb anything that applies to the person rather than the claim, is probably unfair or fallacious, and all X Card arguments apply to the person.
The two most common froms of this variation are the kid and race cards. Routinely people without children or who are of a given race are shunned in discussions of those topics when dissent it offered.
The solider/cop card is gaining in popularity. Mainly it is used in debate about national defense policy or criminal law policy to shut down liberal view points.
This is interesting because we don’t tolerate it under any other circumstances. Indeed in most other areas of life we respect objective distance.
The entire justice system for example is not so much to protect us as it is to dispassionately decide what to do with criminals. Doctors are also encouraged to have emotional distance. And the concept of conflict of interest is at the heart of every contract we sign.
If anyone attempts to eject you from an argument or dismisses a claim of yours based solely on some state of being that you can not or do not possess make sure you’re not being carded.
The work around is to cite the lack of universal agreement among the target group.
Example: You argue with a police officer over drug law, he says you can’t understand till you’ve walked a beat, simply point out the existence of LEAP.
If they’ve said something that the entire target group does (or must) agree with then they’ve probably said something nonsensical, unfalsifiable, or unrelated. in which case you’ll need different tools to shred their point. Google for list of logically fallacious arguments, there are plenty.
