Has to be warm from day one

Do most adult men have *some* attraction to pre-teen children?

No they don't. Absolutely not.

What are men like about this issue when women aren't around to hear it?

They are exactly the same as when women are around. They get angry about it, they don't want to discuss it, and if you talk about it for more than 30 seconds, it will eat away at them until they decide you can no longer be their friend.

I'm just wondering about my odds of being able to be really honest with guys I'm with in the future.

If you want to be with someone with whom you can share ped interests, you should look in the ped community. If you find someone in a "kink" community, you should say what your feelings are right away. Unlike other personality traits, ped stuff can not be overlooked, and it can make a relationship impossible even if he thinks you are perfect in every other way. You've got to get some indication that he's okay with it right away, otherwise you'll be wasting your time and his.