Keep in mind that these were not strictly speaking "Arab raids." Most of the commanders, and almost all of the troops, were of Berber origin, and this continued to be the model throughout the history of Andalusia. Islam may have provided the impetus for the conquest, but it was largely executed by non-Arabs.
Furthermore, if you take the long-term perspective into account, Spain has historically been linked to the Mediterranean (and its southern coast) to an even greater degree than northern Europe. Even if Islam doesn't arrive on time or it never makes it to the Maghreb, that's not going to change.
Indeed, at least the southern and eastern portions of the Iberian penninsula had been in contact with Mediterranean civilization for 1300-1500 years (depending on where you were) with the Mediterranean civilizations (Phoenicians, Greeks and Romans, in that order).
This of course, raises the possibility of a very interesting scenario in the absence of Islam: a (obviously non-Muslim) Berber conquest of Iberia.