Vatican: Indirectly fight communism and dictatorship where possible, while maintaining a strong economy and using it to support freedom fighters and catholic nations.
Switzerland: Become the economy #1 of the world. Build huge forts and anti-aircraft installations along the border. Have the best infantry. If shit hits the fan, take some easily defensible territory of alps from Italy or Germany. For fun sake - take a small territory somewhere in Africa with a small port. (with transit through Italy and airlift, I'd imagine)
Canada: Stay as a part of NATO, while doing nothing for it's sake. Instead, slowly and carefuly frame and 'kill' small countries, colonize them, build military bases, repeat. Somehow take Alaska and perhaps a part of Siberia if a world war breaks out. Be the #1 technologically advanced nation in the world, guarding its secrets well and perhaps even preventing other advanced countries to advance in technology (By sabotage?)
Ireland: Use spies, diplomacy and perhaps guerrilla warfare to free Northern Ireland, fight for the independence of Scotland and Wales.