Exactly what it says, for this scenario assume Russia wins the war in Ukraine within the next year or so and doesn't move back to a non-war economy but instead Putin attempts to go through with plans to win back the Baltic states after a year or two of rest in 2026-2027 in a conventional ground invasion betting that Western Europe and the U.S. won't honor NATO defense agreements and will wimp out on the issue. (Don't argue this)
Also assume also that diplomacy wise Russia enters into secret agreements with many of the U.S. adversaries such as China, Iran, North Korea and perhaps Venezuela to not necessarily fight NATO as a whole but to all jointly take back disputed territories or assault old enemies. (Iran attacks Israel, Venezuela goes after Guyana, North Korea launches an assault on South Korea, China goes after Taiwan.)
How does the U.S. and NATO handle that assuming nukes don't fly?
The issue isn't size of forces of war-time production, but
competence.
And the Russian military is
not sufficiently competent to tangle with NATO.
The blitz towards Kyiv that Russia was trying to pull off in the opening moves of the invasion of Ukraine, especially trying to take Hostomel airport, was them
trying to manage the sort of combined arms warfare that the US and NATO use as a matter of course.
The reason that serious ammunition shortages, especially artillery shells have become such a long-running issue in the war in Ukraine,
is because it's such a long-running war.
So, in a conventional war, on the respective fronts you've mentioned:
If Russia tried to go to war with NATO, based on the capabilities we've seen them display in Ukraine?
Within 24 hours, most of their air force is wiped out.
Within 48 hours, all offensive drives have been utterly crushed, air and artillery support for NATO ground forces shattering Russian morale and unit cohesion.
Within 72 hours, most of Russia's ground-based air defenses have been systematically destroyed, and NATO has started wiping out all military bases within 2-300 miles of the border.
Withing 96 hours, surrender demands are being air-dropped directly over the Kremlin.
By the end of the first week, we're shifting assets out of theater because Russia is absolutely finished as a conventional military threat, and we need to focus more on the Chinese and the Koreans.
If Iran started launching on Israel, and sent a conventional assault force through Iraq, a combination of Israeli and Saudi air power, mostly the former, would do to Iran what NATO did to Russia, except even more easily, because the Russians have
some competent soldiers, whereas the only thing the Iranians seem to be competent at is stirring up terrorists. The US wouldn't even need to get directly involved, though we'd probably have our E-War aircraft and some naval forces acting in support.
Venezuela vs Guyana is honestly a footnote. Venezuela is a poorly-run dictatorship; it probably lacks the competence to take significant parts of Guyana, but even if it does, as soon as a single Carrier task force can be dispatched to the area, they'll get completely wrecked. Given that the international norms about warfare are being thrown under the bus, and they don't have nukes, you could expect the gloves to come off and Maduro to end up very dead, along with most of his key supporters.
China and Korea attacking Taiwan and South Korea is the real question mark.
Most likely, they're not going to be even as competent as the Russians. While the Russian military is rotted out with corruption, they
do have combat experience, and
some of their soldiers are at least decently competent, even if their command structure is wretched beyond belief.
The Chinese haven't fought a war since the 80's, and as a result, while we know they suffer at least
some of the usual issues with communist training, communist manufacturing, and communist doctrine, literally
nobody actually knows just how bad it would all be.
They also have a lot more manpower than the Russians at this point, but the disadvantage of needing to attack across the Taiwan strait.
It's entirely possible that Taiwan manages to fend of China literally by themselves. Amphibious assaults are no joking matter, and Taiwan has been preparing for this conflict for more than seventy years. Their culture also actually supports competence as a concept, rather than suppressing it, and after what happened to Hong Kong, they know
exactly what they'd suffer if they let the Communist boot descend upon their necks.
It's also entirely possible that the PLA is half as good as its propaganda suggests, and there's a real war to fight down there. China still probably won't win, but they'd probably manage to take part of Taiwan, and then half the military ships in the world would be sunk as missiles fly back and forth while they try to support the forces there.
