That all depends. Russia excels in nuclear and radioactive material. If Russia and thee USA were to go to war, yes, Russia would be an absolute threat. Especially for civilian bombing. America excels in air force and navy, and their navy holds the ginourmous Super-Carrier currently making their navy most likely the best in the world. North Korea holds an extremely powerful army. North Korea is also a huge threat to the US, but in a different way. The only other country that posts a small threat to the US, is England. England is the only other country in the world that has the legendary aircraft carriers. England's soldiers are also much better prepared and trained for battle than America's. England trains their soldiers very well. All in all its a matter of opinion. I personally think Russia is the biggest threat. However I doubt any pf these countries would go to war, because that would bring terrible consequences because of the raw power of these nations.
The US counteracted the German's threat to invade Haiti and Santo Domingo by deploying US military in The Dominican Republic in order to protect them and all Americans life.
The globalization of culture
Coal
the terror attack 9/11 is the of the biggest terror attacks in the U.S.
the biggest is the dollar coin and like its name it's worth a dollar
Itself
Nuclear Terrorism
Logging.
death.
There are only 2 big threats and they are polution and loss of foods. Te biggest one can be said is the loss of food.
The US Army is the oldest and biggest branch of military in service, they are also the largest land combat force.
Jellyfish are eaten by squid. I believe that this is the biggest threat that they face.
the market economy was the single biggest threat
Churchill thought that Hitler was the biggest threat in WW2
Biggest threat is a landowner with a 22 rifle or 12ga shotgun.
The military threat grew out of the mutual ideological threat between the west and the east.
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