Only sixty years ago the U.S. and the Soviet Union fought a bitter Cold War to decide what hemisphere and economic/political ideology would be the most influential on the post-WW2 stage. After years of "police action", proxy wars, economic battles, and general geopolitical tension, the Soviet Union fell and the U.S. emerged as the paramount world power.
With the ongoing crisis in Ukraine and increased Russian aggression in the East, many experts believe that yet another Cold War is beginning between the U.S. and modern Russia. Since that no major Western country has actually entered Ukraine to help the invasion through military force, instead the West is fighting an economic war. The large amounts of economic sanctions that have been placed on Russia and its most rich citizens is meant to totally isolate Russia from the contempary market economy. Banking sanctions are the most notable way that economic pressure can placed on Russia. In response, the Russian government has sought out allies to help keep their economy secure, the most notable being China and other OPEC nations that tend to side with Putin's regime. This comes while most Russians are suffering through these drops in living standards while their government continues an unpopular war.
For now economic weapons appear to be the main way this war is being fought on an international level, one should hope that more direct means of intervention are not needed.