America is merely trying to consolidate its position as the worlds only true superpower...it does this on a very shrewd level...any countries who deal with russia and china do so under the watchful eye of america...if the deals these countries do with "the enemy" are thought to be affecting americas power them america simply cease trade with those countries safe in the knowledge that america can decimate a countries economy by refusing trade and thus keeping that country in the gutter
this is a double blow to russia in that america can stop countries trading with them and also keep the russian economy in serious problems
a very effective strategy indeed