Hello Dads out there, new poster here.
It's been pretty quiet on the forum so I hope some of you still check in here.
Anyways, I have struggled with these thoughts just like the original poster.
A little background, Im 36 and my wife and I just had our first child 5 months ago, a beautiful healthy baby boy

I think the first time I had a "scary thought" came from a book I was reading about 3 days before he was born, there was a scene in it that really disturbed me (I wont share it as to not add any triggers for anyone else) so much that it gave me tons of anxiety for a few days. It disturbed me so much I started wondering "Is there somethiing wrong with me?" I started thinking things like "geez, since it bothered me so much could I be capable of doing something like that?" Well eventually it went away and I was fine for a while....
Then every couple of weeks it seemed the heavy anxiety came on again, and things that were scary or dangerous would make me think of awful things regarding my baby, sometimes unintentional harm and sometimes intentional.... I would even question "Could I actually do that? Am I going crazy?" Honestly I hated myself over the thoughts, I thought I was either going crazy or an evil person.
I kept it to myself for the first few months because I was terrified what my wife or anyone else might think. It went on long enough I started looking up things on the internet and thats when I found out that scary thoughts regarding your baby are apparently normal and common in both fathers and mothers. I wonder if it would have affected me less if I would have known that from the start. I love my kid so much and the thought of doing something to hurt him is about the worst thing I can imagine, and I think that might be what heightens the anxiety.
I found a book called "Dropping the baby and other scary thougths" by Karen Kleiman. It's directed at mothers suffering from these thougths, but amazingly almost all of my feelings where right in the book. The only issue I wondered about was that its directed at Mom's and did all the info apply to a Father as well. That's when If found this forum.
Anway, is the original poster still around? If so, how are you doing now? I hope you have been doing well because I can understand how terrible this can be.
One of the most important things I took from the book is "Its not the content of the thought but how much it disturbs you thats important. Basically that scary thoughts are just that "thoughts" and they arent you and if you are disturbed by them then its quite normal.
I still occasionally get anxiety on and off and now its mostly worry like "Is there really something wrong with me because I dont want to have these thoughts anymore". Im doing much better but its still a bit of a struggle. It's the whole "Dont think about that thought" so you know what happens thats what you think about!!!!
Completely agree with you all regarding the news stories and stuff, I mostly avoid the news now because stories about bad things happening to children disturbs me too much.
Anyways, sorry for the long post its not easy to sum it up quickly and not easy to open up about this stuff. Hopefully some other guys that have had similar thoughts will see this and get some reassurance and maybe post their experiences here.