What other countries besides France could have plausibly colonized Algeria, with any PoD after 1715?
Any of the countries listed a plausible alternative?
Spain, Britain, Naples/Two Sicilies, Piedmont-Sardinia, Austria
If none of these are plausible, could Algeria have plausibly remained independent through the 19th or 20th century?
...and, as a minor aside, interested in an additional question-
How plausible would it have been for France that did conquer Algeria to exercise a "mere" protectorate over it, never encourage mass settlement, and never adopt the position that Algeria was part of of metropolitan France. Instead Algeria would be administered more like Morocco or Tunisia.