With the seas heating up around them, Tokyo and Seoul are considering their next moves. Accelerating geopolitical trends, from the Chinese navy's continued development to North Korea's nuclear program , are driving Japan and South Korea, two key naval powers in the Western Pacific, to evaluate plans for the development of aircraft carriers. However, both appear to be pursuing a more restricted strategy because of their limited military budgets and — in Japan’s case — the constraints imposed by history. Nevertheless, their serious consideration of this naval expansion attests to the heated maritime competition in the region. Dipping a Toe in the Water Japan once fielded one of the best carrier fleets in the world, but its past capabilities on the sea have hindered, more than heralded, the return of a carrier fleet.