Chris Mark is a veteran of the US Marines, co-founder of the Mark Consulting group, and the writer behind the Global Risk Info blog covering various securiity topics—but today, he's one of the most prominent critics of Sarah Palin's recent decision to blame her son's domestic violence on PTSD and President Obama. Usually, Chris and his wife Dr. Heather Mark weigh in on matters of international security or large news stories about the US military, but the recent story of Sarah Palin's response to her son Track's arrest prompted Chris to write an open letter to the briefly-tenured Alaska governor. Here's Mark's letter to Gov. Palin:

Sources: Global Risk Info