# BCS Theory of Superconductivity

I'm currently taking an introduction to Solid State Physics class, and is now on the subject of superconductivity (SC). Currently I'm reading about the BCS theory, and how this works on a microscopic scale. I then get presented with this picture (Electron-Phonon Interaction):

Now, as far as I have understood, the electrons, when below $T_{C}$, attract the ions, but are too fast compared to the ions, which means that the ions contract after the electron is gone. This creates a higher potential in the area where they are "squeezed" together which the next electron is much more attracted to that usually. This again means that all electrons pretty much follow the same path, and somehow bond together in Cooper Pairs (Is this the way they get entangled?).

Now, my main question is: Does this attraction of ions, after an electron has moved past them, not happen to a normal metal ? I mean, the electrons move in a normal metal, and also past ions. So don't they attract the ions as well, and make this attraction that another electron then can follow as well ?

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