AP's poor choice of headlines

In a story about old atrocities committed in another country by non-Americans, you'd think the title would identify the perpetrator of the atrocity directly. Not AP, though. Check this headline:

Here's some of the article itself, nearly as bad:

DAEJEON, South Korea - Grave by mass grave, South Korea is unearthing the skeletons and buried truths of a cold-blooded slaughter from early in the Korean War, when this nation's U.S.-backed regime killed untold thousands of leftists and hapless peasants in a summer of terror in 1950.

With U.S. military officers sometimes present, and as North Korean invaders pushed down the peninsula, the southern army and police emptied South Korean prisons, lined up detainees and shot them in the head, dumping the bodies into hastily dug trenches. Others were thrown into abandoned mines or into the sea. Women and children were among those killed. Many victims never faced charges or trial.

There's always a way to blame America, isn't there?

You could also see this as a "name that party" exercise from history - can you guess who, in 1950, was in charge of the US military and his party affiliation from the article?