During just wars, just groups have good reasons for plotting in secret. Some other groups also have justifiable reasons for plotting in secret.
The phrase conspiracy theory is a combination straw person and circumstantial ad hominem attack used to dismiss opponents and treat them as mentally unhealthy. The phrase is used equivocally, meaning crazy, preposterous or a secret plot (or all three), often by establishments to associate critics with those who believe in alien abductions or other preposterous ideas. Calling alien abductions a conspiracy theory has little ethical importance. But the conspiracy theory phrase is a big deal when used to demonize well-reasoned political criticism.
Today, many facts get treated by establishments as "conspiracy theories." To name a few:
- Marxian states failed to return some allied POWs.
- Cultural Marxism not only exists, it is the major form of Marxism, with 71 percent of college freshmen opposing speech freedoms, but not their own speech freedoms, of course.
- Fast jihad is Islamic and is done by Muslims.
- We live in an intellectual climate far worse than McCarthyism. (The linked list is a fraction of those punished or threatened with punishment.)
- Nonwhites have worse ethnoracial behavior than whites and their behavior gets worse when their numbers increase.
- Words have more than one meaning: Jihad means both inner struggle and anti-Infidel totalitarianism, though the former meaning is used for equivocation to fool infidels.