If Russia is careful not to attack NATO countries, will occupation of west of Ukraine by USA end the war? [closed]

Question

NATO countries are very careful to not attack Russian forces in Ukraine. The main rationale given for this is "Russia has nuclear weapons. Attacking Russian forces might lead to a nuclear war."

Similarly, it seems that Russia is very careful to not attack NATO countries. One excuse for attacking Ukraine is that "it wants to join NATO", but other countries - which already jointed NATO - are not attacked. Probably, the rationale is similar: "NATO countries have nuclear weapons. Attacking them might lead to a nuclear war".

Now, suppose the USA (or another NATO member) invades Ukraine from the west, and occupies all the territories not currently occupied by Russian forces. Now, apparently, there is a symmetric condition: two occupying forces, both have nuclear weapons, both are careful to not attack each other in order to avoid a nuclear war. So the hot war will end. For Ukraine, this situation will be much better than being entirely occupied by Russian forces, so they might agree to this plan.

Is this consideration correct? If not, then where exactly the symmetry breaks?

NOTE: I understand that my "idea" is probably too naive, I just want to understand where exactly it fails. Why is this not a symmetric situation?

Answer 1

I answered a slightly different question with

[...] There are a number of requests and suggestions which come down to let's have a war between the West and Russia, so Ukraine doesn't stand alone. They include

• immediate NATO membership,
• immediate EU membership,
• NATO air forces over Ukraine to enforce a no-fly zone,
• NATO air defense forces in Ukraine to enforce a no-fly zone,
• NATO ground forces in Ukraine to protect people.

[...] So the proposal comes down to a war between the NATO members and Russia. An entirely understandable request from Ukraine, who are in the war, but countries not yet at war with a major nuclear power might hesitate a bit. [...]

I did put NATO troops defending Ukraine on the list. It doesn't really matter under which label those troops come, as long as there is a significant number of combat troops.

Elsewhere I answered

One can debate going to war over Ukraine, but please do it with open eyes.

Answer 2

It is a plausible scenario. NATO would not want to share a border with potential Russian military client state. They would need a buffer zone and that may lead to the partition of Ukraine (google for many maps) and may eventually end the war.

It's hard to tell how probable that is.

In this case, NATO forces would enter Ukraine and will probably have under-the-table agreement with Russia about that.

Answer 3

Probably not because Russian troops surround some large Ukrainian cities. According to UK's MoD as of this morning

Kharkiv, Chernihiv, Sumy and Mariupol remain encircled by Russian forces and have experienced heavy shelling.

There would be no way for Western troops to peacefully get in and establish the equivalent of West Berlin(s) in these areas, unless the Russians agreed to that.

So war/sieges will likely continue in more than half of the country.

As for how Putin would react militarily to NATO troops crossing Ukraine's border that's very much open to speculation, but it would certainly help his narrative that Ukraine is a NATO puppet etc.

Also, your question is extremely hypothetical not only because the lack of NATO will to do such a thing, but also because Western NATO forces are present in quite low numbers (tens of thousands) in Eastern Europe, with barely 100 tanks or so. Eastern NATO members have militaries quite inferior to Russia's both qualitatively and quantitatively. It's quite uncertain they'd even be capable of a large scale peacekeeping operation, as Ukraine would require.

Flying NATO troops into Ukraine in sizeable numbers is most implausible because Russia can bombard airfields with cruise missiles etc. Assembling a credible NATO force on the ground in Eastern Europe will probably take months. See how long the preparations for Desert Storm took, for instance, or what the fuel requirements were.

Seeing the build-up Russia could pre-emptively invade Eastern Europe countries too; it has a direct border with the Baltic countries. Speaking of which, the scarcity of NATO ground forces facing Russia in that sector is a perennial discussion issue for Western planners and pundits alike.