A new report shows a trend of increased defense spending among Asia's major military powers, with China's military budget nearly half of all spending in the region. It's a trend that reflects one reason why the Pentagon is heavily focused on increasing its presence in the region.

According to official reports from China, defense spending there has increased to $90 billion in 2011 from $22.5 billion in 2000. It should be noted that skeptics believe China's official numbers are purposely low. For example, the Stockholm International Peace Research Institute estimated that China's 2011 defense budget was much closer to $142 billion.

Either way, there's no doubt China is spending more on defense. That growth helped China surpass Japan in 2005 as the biggest defense spender in Asia, according to a study of Asian defense spending released this week by the Center for Strategic and International Studies.

The nation now accounts for 40% of military spending in Asia.

But China is not alone; all five of Asia's military powers, including India, Japan, South Korea and Taiwan, increased their defense budgets, especially in the past six years. The Center for Strategic and International Studies estimates that by the end of this year, Asia will be spending more on defense than Europe.

This trend will likely continue, according to the center, because several nations are investing heavily in high-cost weapons systems, including India's Multi-Role Combat Aircraft, and Japan's planned purchase of at least 42 F-35 Joint Strike Fighters.

But consider this, if you combine the defense budgets for all five top Asian nations, it adds up to about $223 billion for 2011 ($275 billion if the Stockholm institute's estimates of China's spending are accurate). That's less than half of the United States' planned base defense budget (not including spending on the war in Afghanistan) for 2013.

It's also important to note that defense spending is not a very good predictor of a nation's success on the battlefield. As Winston Wheeler of the Project on Government Oversight pointed out last week, "If spending or the size and breadth of forces were the sole determinants of success, the British and French would have won in 1940, the Russians would have repelled the Germans in 1941." He also pointed out that the American colonists never would have beaten King George's army and navy if defense spending were a good indicator of military success.