This article presents an approach termed ``radical geopolitics'' that addresses two of critical geopolitics' blind spots, namely, its lack of attention to the causes (the ``why'') of policy and its neglect of political economy. In particular, it examines the respective roles of the geopolitical and geoeconomic factors that drive policy. The argument draws on David Harvey's ``logics of power,''modified and reformulated into a ``geoeconomic logic'' and a ``geopolitical logic'' through which postwar American foreign policy may be interpreted. The former logic arises out of capitalism's tendency to expand geographically and the latter out of politicians' need to maintain credibility internationally as well as from electoral pressures at home. A discussion of the Iraq War illustrates the approach and illuminates issues overlooked by critical geopolitics analyses, in particular: Why did the US invade Iraq in 2003? And what was the role of oil, if any, in motivating the invasion? It is argued that Iraq was invaded to control its oil (but much less to use it for US consumption, and still much less to generate profits from it), and to maintain American credibility. Radical geopolitics should not be seen in opposition to critical geopolitics, but rather as seeking to supplement its analyses through discussion of issues which have received less attention.