Adding European nations to NATO has not increased the European contribution to NATO. Write David Grantham and Christian Yiu: “After the last expansion in 2009, NATO’s defense expenditures per capita increased 2 percent, and spending per square kilometer decreased by 11 percent[.] […] In 1990, the 14 European members of NATO spent around $314 billion on defense, but in 2015, the 28-member organization spent only around $227 billion on defense (before adjusting for inflation). According to the Carnegie Endowment for International Peace, while European membership in NATO nearly doubled, defense spending by member states decreased 28 percent. That means the United States picked up the tab. NATO says in a discussion of indirect funding that ‘the volume of the US defense expenditure effectively represents 73 per cent of the defense spending of the Alliance as a whole.’ […] Europe’s combined GDP and population is $19.79 trillion and 552 million, compared to $17.95 trillion and 323 million for the United States.” [Internal citations omitted.]
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