"It has been a long while since the United States had any imperialistic designs toward the outside world. But we have practised within our own boundaries something that amounts to race imperialism"

Wendell Willkie's quote addresses the contrasting nature of the United States' external and internal policies worrying imperialism and race. To start with, he acknowledges that the United States has actually not just recently pursued imperialism in the traditional sense on the global stage. Historically, imperialism involves asserting control over foreign areas and peoples, often for financial or tactical benefits. By mentioning that it's been a long while considering that the U.S. engaged in such actions, Willkie might be alluding to a shift in foreign policy or maybe referring to the then-recent past where America's imperialistic tendencies were typically directed away from territorial conquest and more towards impact and global existence through diplomatic and economic means.

Nevertheless, the 2nd part of the quote introduces the concept of "race imperialism" within the United States itself. Here, Willkie explains an internal kind of domination and control: systemic racism and racial inequalities that prevail within the country's borders. This phrase suggests that within the U.S., there exists a system where one race puts in superiority and control over others, reminiscent of the hierarchical control seen in standard imperialism. In spite of advocating freedom and democracy globally, internally, racial minorities go through a pervasive condition similar to being colonized within their own nation.

Willkie's usage of the term "race imperialism" is a powerful critique of the social and political environment of his time, highlighting the contradiction in between America's democratic perfects and its racial truths. It recommends that while the country may avoid external supremacy and colonization, it stops working to deal with significant problems of racial justice and equality in the house. This duality presents a moral paradox where the pursuit of equality and justice abroad does not line up with the domestic treatment of racial minorities, hence requiring self-questioning and reform within.