[bmm6o]

The short answer is that there would still be tides without rotation, but with a period based on the lunar cycle. We have daily tidal effects, the moon can't do that by itself.

[kadoban]

Ah I see, that makes sense. Thanks.

[thaumasiotes]

The mental model I was presented with is that the ocean bulges toward (and, on the other side of the earth, away from) the moon, and the earth spins within the ocean. If you take a perspective that is fixed to a particular point on the earth, you'll see the tides constantly moving past, but that's an illusion just like the rising and setting of the sun. They're both really the rotation of the earth.