It's also a pretty uniquely North American approach to assume that you will be the only 'game in town' when the balloon goes up, so you need to be fully self-contained, which can be extraordinarily wasteful and isolationist while ignoring all the benefits that a strong foreign policy/ diplomatic arm can accrue to any intervention force.
As far as the Americans are concerned it makes sense to have that attitude. Very few countries bring the esoteric enablers to the table that the Americans have. Most of the Western European countries don't even have the standard enablers such as artillery of any consequence. Surprisingly it's taken this Ukrainian war to show that while they might have been dealing with old kit, some of the former Soviet block have continued to maintain a more balanced force.
As far as Canada is concerned; well ... we gave up the fully self contained concept a long time ago in dribs and drabs holding tightly to our infantry core. The Navy has very little jointness to it while the Air Force is hanging in there but just.
I don't have my finger on exactly how badly off our logistics system is, but my general impression is that its pretty close to being on life support. It was severely strained in Afghanistan supporting one battle group and a bloated brigade headquarters and, if I understand correctly, has gone downhill from there. We have three functional brigades but can't sustain even one for long.
Currently re-reading Conrad's book and taking a closer look at the issue. I'd forgotten how negative his views about the Army's leadership's attitude to logistics were.
Some European forces, for example, plan on having 'host nation' support when they get on the ground wherever they're going, in some way, whether that be through wepons, armour, logisitcs vehicles and other similar support. This can be a huge load off of the military side of the force.
Planning on having that host nation support greatly limits the operations that you can participate in because the nature and extent of such support, if it exists, varies greatly. It's wonderful if its available, and as you say will take a load off, but I think any prudent force structure needs to be built on the assumption that support will be nonexistent in at least some circumstances. This is why the US still has some ship-to-shore terminal battalions and a Marine Corps.