Clearly, focusing on the numerous times someone has themself been wrong is unlikely to help, but conveying the fact that we have been wrong too might. People should feel that they can remain or become secure, safe, respected, and loved while dropping their misguided belief, and without substituting a new zealotry in favor of another belief (even ours!) -- that they can become more cautious, more willing to remain in doubt, and more willing to continue that way in the face of the certainty of others. Ideally, people should be urged toward better beliefs by a friendly and welcoming and large group of others. There's no reason peer pressure can't be put to good use, even while seeking to reduce its power.
More importantly perhaps, an ounce of prevention is worth a pound of cure. If we can prevent people developing attachments to lies about Syria or Iran, we will save ourselves endless headaches trying to rid them of those lies later. If we can establish not just that Iraq was unarmed but also that Iraq's being armed would have been no justification for bombing its people, we will shift the conversation onto favorable ground. If Syria killing Syrians with the wrong kind of weapons is understood not to justify the United States killing more Syrians with the right kind of weapons, we won't have to engage in a fast-break competition to determine and then prove whether Syria is using weapons that the United States claims it is using.
The preceding paragraph is the theme of a book I wrote called "War Is A Lie," which I intended for war preparedness in the sense of preparation to resist common types of lies about wars. In that book, I did not follow all of the advice above. People in fact have complained to me (a small minority of readers I should say) that the book is at times sarcastic or mocking or contemptuous. In my defense, I see a value in entertaining as well as educating those already in large agreement, as well as in reaching through as powerful a manner as possible those without ossified views on the subject. But then again, there is always and forever the possibility that I'm horrendously wrong.
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