Steve, colonial involvement by France was similar to our own foreign policy . The policy is dictated by who is on the inside and who is making what money. The novel Bel Ami by Guy de Maupassant is a story of how the business interests who owned the media crafted their message like a facebook persona. The "news" of the day was nothing more than a narrative to serve a specific set of interests, not unlike our news media today. Pretty funny book.
What it really boils down to is an unsustainable birth rate that has reached a tipping point. The desert countries of North Africa and Asia Minor cannot support their populations. Not enough land, water, and commerce. The big boys are still gonna rake in the cash while ordinary people get stuck with the consequences.
We have to be honest about the tremendous pull of political correctness, of which France is the birthplace. Portugal has an equally nasty colonial past yet isn't the magnet for Muslim violence.