Why exactly isn't this also true of the French Empire, though?
No. The French had an ideology that could adapt to what its Empire needed to become (and indeed the Left and elements of the far Right were actively pushing for French imperial policy to shift in ways that could accommodate an "Empire of 100 million Frenchmen").
The British had a far less open ideology and I'm not aware of any major political groups in Britain that pushed for reform in a useful direction. There was considerable resistance to making the black and brown subjects of the crown British citizens.
Also, the British had already promised independence or given independence to pretty much everywhere that counted in their Empire before WW2 had even begun (i.e., the white Dominions, India and Egypt), without those, the bulk of the rest of the Empire was not profitable enough for the British to desire to keep it. I guess the British might have wanted and had the power to keep Malaysia without a Pacific War. The British might have also done better in the Persian Gulf.
In contrast, the French had not promised anyone independence before WW2 and had reasons to want colonies that weren't profitable in monetary terms.
Also, what about Tunisia, Morocco, and French Sub-Saharan Africa?
I already mentioned all of these.
Or do you mean in the sense of all of these being disasters waiting to happen? Well, they could have gone wrong. But Algeria would need a miracle to avoid becoming a mess. Everywhere else would take a pile of bad decisions to become similar messes.
Wouldn't there be too many Vietnamese people to make all of them French citizens, though?
That's exactly why I doubt France could integrate them into a commonwealth effectively. They'd need to be very accepting very fast and the Vietnamese had very little patience left (but unlike India, there was some patience left before WW2).
Wouldn't Vietnam oppose this since it would view both Laos and Cambodia as a part of its own sphere of influence, though?
Sure. But without a German occupation, the French are much stronger so are better able to set the terms. I'm imagining that at first, Laos, Cambodia and Vietnam would all be protectorates that had little independence (as the French tried to do in OTL after WW2), but I reckon Vietnam would shake loose from that as the French just didn't behave in ways that fit with Vietnamese interests - but as Vietnam shook free, it would push Laos and Cambodia closer to the French.
Of course, French stupidity here could put them on the path to a bitter decolonization and subsequent expulsion from the region. I'm not entirely sure my optimism here is warranted, since the French could be less open to the large changes made in Indochina in OTL (which in OTL weren't radical enough, but without Japanese occupation might have been acceptable and enforceable).
Why exactly would Syria be deeply integrated into the French economy?
Because the French were heavily invested in Syria and even in OTL, French companies were very active there.
In TTL, French investment would be much stronger and harder to dislodge, even if French political control was doomed.
Also, though, what about Lebanon?
My bet, de jure independent and due to heavy cultural and economic penetration, de facto part of the French Empire.
Question--would all of the people inside of the French Commonwealth hold French citizenship, or what?
That's certainly what the Left would be pushing for. Alternatively any part of the Empire to have "French Commonwealth" citizenship alongside "French" or "Senegalese" or "Malian" citizenship - basically so that French governments could have more control over immigration between regions even as they welded everyone together into a "megaFrench" nation.
The French view of themselves at this time was not as a "race" as the British or Germans conceived of themselves, but as a superior culture, which welded together a diverse European homeland and could weld together a diverse world empire (and of course, the ideals of the Revolution were an outgrowth of that culture, so to truly understand freedom and brotherhood you needed that superior culture and that superior culture would enable more freedom and brotherhood).
Wasn't Morocco independent for too long to permanently be a French protectorate, though?
No, I don't think so. The main variable is not how long Morocco was independent - the variable is how much respect the French accord to the Moroccans.
OTL, after a bad start, the French did well in this, which is why Morocco integrated so deeply into the empire, despite being a late addition.
The French could mess this up, of course. But I suspect what would happen is the French would allow themselves to be pushed out of the areas that didn't matter so much to them, and what would be left is a Morocco in extremely close alliance with France, French military guarantees, heavy French economic penetration and heavy cultural inter-weaving (with Moroccans in France and French culture popular in Morocco).
Out of curiosity--how large were pro-independence sentiments in West Africa in our TL?
Low. Kinda. West Africans had an interest in their own self-determination and an awareness of their own interests. But the French succeeded very well in selling French culture to the elites in the West African colonies.
So when it became in the interests of West African states to be independent, the whole thing gained momentum, at the same time, the elites gladly retained close ties with France and there are hints that even with France as weak as it was, had international politics been different, West Africa might have retained closer ties.
Also, specifically, what do you think (in detail) decolonization in British India, Palestine, the other British Middle Eastern colonies, and the British African colonies would look like in this TL?
That depends very much on what WW2 looks like.
The messier WW2 is, the messier decolonization is.
fasquardon