I think it's an error also. The lettering seems to have been stamped ON the error and not crushed by some kind of PMD. But what kind of error, I haven't the foggiest. I'm not that knowledgeable about how errors happen.
That's because it is not an error. If it were double struck the side opposite of the strike would be blank. Uniface. The letters definitely look incused to me.
The problem with letters like A, Y, T, and I is that they have the same shape backwards and forwards, so the shape and positioning of the letters really cant be used as a basis to prove a brockage or double strike exists. To me, this has all the signs of a post-strike alteration.
Damaged. For the reasons listed by others. You can see some flattening on the obverse rim opposite the squeezed area.
A good photo of the third side of the coin might give us more information. @amnight, can you give us that?
Here are some more pictures of the coin. I have included the third side where the damage is. I also would like to know why the right cross of the "T" in "UNITED" looks like it angles downward. I would also like to thank everyone that contributed to this post!
Thanks to all for taking the time to explain this coin. My depth perception is working overtime. Lol I’m glad the members that did respond took the time to explain as I think we all learned, or should have, about this type of error or in this case, PMD. I would think this was damaged in a vise to get what I see on the rim in the upside letters. A good coin to learn from.