There is some controversy over the current strategic concept of military ‘forward presence’ in the Western Pacific in order for America to project power and continue to maintain its and its allies security in the region. There are some who think that ‘offshore balancing’ should replace this costly military strategy. Offshore balancing basically means letting other nation-states in a region of the world deal with any aggressive hegemon in that region.
The problem with the concept is that this approach tends to lead to an arms race among many of the stronger countries in the impacted region which then destabilizes the security environment, making armed conflict more likely than less. The concept also presumes that if offshore balancing is not successful that America would come to the aid of its allies in that region if they were not able to deal with the hegemon on their own. Offshore balancing is what America initially tried to do during the First and Second World Wars however that resulted in a very deadly although ultimately successful outcome. While America was able to become a force in ending those wars, it came at a terrible cost in lives and treasure because America had to fight to take back territory that the enemy had already seized.
So, while maintaining a military forward presence in the Western Pacific is expensive, it is the least risky concept for America to continue to follow. In fact it has worked to prevent any major near-peer war in the region since the end of the Second World War.