Wargame: Twilight 2000 as expanded upon by the other posters
Wargame; Fortress America!
I do own a copy of the re-released version, it is quite fun.
And maybe a near future Wargame(2020-2030)
Breakdown of old alliances due to economic strain.
Pan-Atlantic coalition: US, UK, Canada, assorted smaller nations assimilated.
Northern EU+Austria Swiss: After the economic collapse of southern EU nations, nrtherns form seperate economic/military pact. Germany, Viking nations, France. Member's militaries are small. Expert Mountain Troops, many great fighters, no super fighters. Armored units are well armored but also speedy, many APS systems on all vehicles. Survivable.
Southern Europe: I do not have any ideas here.
Balkans(Except Albania, Greece) and Russia,Belarus: Pan-Slavic Union: Russia makes up the armored bulk, while Balkan nations bring in experienced troops from various local wars. Belarus brings quirky indigenous stuff.
Poland, Slovakia, Czech Rep., Ukraine: Military equipment is a mix of the modernized soviet gear upgraded with cutting edge western tech from the time spent in NATO. Infantry has high morale as fighting to stop Russian encroachment. Tanks are modernized with great ammunition. However, one can only throw so much armor on a T-84 or PT-91. Heavy AT weapons are carried by most infantry, whose wheeled IFVs(Pandur, Rosomak II, etc) are equipped with at least a dual ATGM launcher.
Chemical warfare, tactical UAVs, electronic warfare. Towed weaponry, deployable weapons.
"The Nazis entered this war under the rather childish delusion that they were going to bomb everybody else, and nobody was going to bomb them [. . .] They sowed the wind, and now, they are going to reap the whirlwind."