World War 3 scenario:
UK
France
Italy
US
Poland
Ukraine
Canada
Australia
Israel
S. Korea
Japan
Turkey (maybe)
Germany as non combatant support (munitions)
Versus
Russia and loyal Federation states (Belarus and the "stan" countries)
China
Vietnam
Iran
Syria
N.Korea
Venezuela as non combatant support (no oil sold to US, more to China and N. Korea)
Russia and China could be looking at this moment in time (US war weary and depleted, other G-7 military capabilities less formidable) as their chance to shift the balance of world power to their favor.
India would want to side with whoever is against China, and Pakistan will want to side with whoever is against India...
All highly unlikely, of course, but then WW2 seemed highly unlikely...