Glassy, your post seems to be have been cut off ...
Quick answer; there is no quick answer! - the connections been Arabic and Andalusian music, are pretty complicated. The Andalusian Gypsies, the standard thing goes, came there from North India (via Egypt, or at least popularly assumed to have, hence the name), but the similarity between North Indian and flamenco musics must be more complicated, because the sound world of North Indian is heavily derived from the Arabic influence taken there by the Mughals, which must have been after the Gypsies travelled west. At least, the reason I say that is that South Indians of my acquaintance make a strong musical distinction between the southern style, with little or no 'arabic' component, and the northern style, which has lots (the euphemism was the northern sounded 'sad'). Before I get completely out of my depth and write something completely ridiculous perhaps some of our Indian 'Campers might like to set this straight.
So I think you will find it is that the Andalusian sounds Arabic.
Re modal vs harmonic, well depends on definitions. You may have noticed that many of these other musics have little or no harmonic change; classical Indian for example plays over a drone. But modes e.g. scales exist in the western tradition, so as so often its about where one draws lines. By Western music typically one means the music of Europe and its off-shoots to the US etc, and it normally implies Classical music from Bach onwards though again it depends on the context.
Simon Ambridge Series 40 (2005)
Trevor Semple Series 88 (1992)
Louis Panormo (1838)
Alexander Batov Baroque Guitar (2013)