I was reading a book on QFT and the example he uses to make an analogy of spontaneous symmetry breaking in QFT is that of the rod where a compressive force is applied on the top surface of the rod directed down the axis of the rod in line with the rod's axis.
The rod bends and is no longer rotationally symmetric. I don't really understand how it is "spontaneous". I did a little more digging and someone else who uses this example states that SSB does not require an external force and as an example he showed if you apply another force tangent to the top of the rod, this also breaks rotational symmetry but isn't spontaneously broken. But both of these examples use a force to break symmetry of the rod. Why is one not spontaneous symmetry breaking but the other is spontaneous symmetry breaking, since they are both the same thing - applying a force to break symmetry?