In a non-nuclear war, The United States has the advantage of superior military power, and technology, and having Alaska as a staging ground. While Russia, has no advantages. If Russia had invaded, then they would have to march through Canada first before being able to reach Mainland USA, and the Canadians wouldn't put up with that. While if the US invaded Russia, The Russians have the advantage of the Russian winter, knowing their battlefields, and having almost no route from Vladivostok, to Moscow.
In a Nuclear war, Neither, both countries would be so damaged from nuclear warfare, that they would both be nothing but wastelands.
But in a non-nuclear war, it all comes down to the tactics used.
Russia and China are in Asia. Canada and the United States are in North Amarica
Russia has a much larger military. Russia.
Russia
africa germany canada united states of amarica china russia
africa Germany Canada united states of amarica china Russia
i would say russia because there a very big country
Probably China. There are many discussions about this, look online.
Asia is not unified at all and Russia is in Asia.
Today clearly the US.
Russia. They have way more nukes then China.
Russia. Russia could defeat any country except America and China, with or without nukes.
there are about 14 countries of the whole of south amarica.