A "Memo From Brussels" about American defense spending and Europe's includes the following passage: "France says that by 2014 it may cut deeper still — to just 1.3 percent of G.D.P., down from 1.9 percent this year. By comparison, the United States spent 4.8 percent of its G.D.P. on the military in 2011."
Comparing 2014 or 2013 to 2011 is an apples-to-oranges comparison. If the Times wants to compare the United States and France, it should compare what the U.S. spent in 2011 against what France spent in 2011, or what the U.S. says it will spend in 2014 against what France says it will spend in 2014, or what both countries are spending in 2013.
As it turns out, according to this spreadsheet from the White House Office of Management and Budget (the Times article, typically, doesn't provide either a source or a hyperlink for its statistics) — the White House says that national defense spending as a percent of GDP was actually 4.7 in 2011, not the 4.8 the Times claims. For "this year," or 2013, the estimate is 4.1 percent. The estimate for 2014 is 3.7 percent, and for 2018 is 2.8 percent. So it is not only Europe that is projecting defense spending will shrink as a percentage of GDP.