The Washington-based Center for Strategic and International Studies on Tuesday said China's defense spending totaled US$89.9 billion this year, a four-fold increase compared to 2000. Over the last 10 years, China’s annual defense spending increased 13.4 percent on average, much higher than South Korea's (4.8 percent) and Japan's (3.5 percent).

The CSIS believes China's official defense spending figures probably represent only 60 percent of what was actually spent. British defense consultancy IHS Janes forecast that it will amount to $238.2 billion in 2015, which is more than the combined defense budgets of 12 Asian countries including Japan, South Korea, North Korea and India.

China launched its first aircraft carrier this year and plans to commission three carrier fleets by 2020. Japan is also on course to bolster its military spending as Liberal Democratic Party leader Shinzo Abe, who is widely expected to become prime minister again, calling for the country's pacifist constitution to be revised so it can invest more in arms development and procurement.

China is bolstering its military hardware with the excuse of preparing to deal with an increased U.S. military presence in Asia, while Japan is following suit to keep China in check and counter the North Korean threat.

South Korea simply does not have the money to compete with the world’s No. 2 and 3 economic powers in the arms race. Yet any attempt by Seoul to drastically strengthen or weaken its alliance with Washington could draw either a hostile response from China or risk alienating it in Northeast Asia by pushing the U.S. aside.

The presidential candidates appear to believe that efforts to resolve historical disputes in Northeast Asia and greater economic cooperation will automatically lead to stability on the Korean Peninsula. That sounds good in theory, but the fact is that South Korea could face a serious threat depending on geopolitical events that can erupt at any time.

Former U.S. secretary of state Henry Kissinger said a country must forge its security strategy by objectively analyzing the national power and military presence of its rivals rather than on the political will or good faith they seem to be showing. Kissinger used as an example Germany's military preparations in the early 20th century. Pundits at the time forecast that Germany would emerge as a threat to the U.K. once it gained the upper hand in terms of military power, regardless of its goodwill or apparent lack of belligerence, and the start of World War I proved them right.

Should South Korea's presidential candidates continue to turn a blind eye to defense and continue to fixate on unrealistic ideals, then the day may come when the country pays the ultimate price. The public must grasp the changing political climate in the region and ask which candidate has the right security strategy before they head to the polls in December.