In the first half of the 20th century, and more actively in the post–World War II period, the United States government used economic aid programs to advance its foreign policy interests. US policymakers generally believed that support for economic development in poorer countries would help create global stability, which would limit military threats and strengthen the global capitalist system. Aid was offered on a country-by-country basis to guide political development; its implementation reflected views about how humanity had advanced in richer countries and how it could and should similarly advance in poorer regions. Humanitarianism did play a role in driving US aid spending, but it was consistently secondary to political considerations. Overall, while funding varied over time, amounts spent were always substantial. Between 1946 and 2015, the United States offered almost $757 billion in economic assistance to countries around the world—$1.6 trillion in inflation-adjusted 2015 dollars. Assessing the impact of this spending is difficult; there has long been disagreement among scholars and politicians about how much economic growth, if any, resulted from aid spending and similar disputes about its utility in advancing US interests. Nevertheless, for most political leaders, even without solid evidence of successes, aid often seemed to be the best option for constructively engaging poorer countries and trying to create the kind of world in which the United States could be secure and prosperous.