$118bn was spent funding police forces in the U.S. in 2018, according to the Security Policy Reform Institute. It collectively makes American police forces the world's third-most expensive military organization, after the U.S.'s official armed forces and China's.
The chart is somewhat misleading, though, in that the same is basically true of other wealthy countries: per-capita spending on police in Europe is also very high, but the countries are less populous. Police forces in the UK enjoy some $25bn in funding, for example, a spend proportionate to the US total that nonethless places it outside the top ten on the that military spending chart.
But there's one thing that's plainly different: US police are militarized by policy, trained to treat the public as a threat, and kill people in far greater numbers than their foreign counterparts. The declared enemy of American police forces is the American people, and their war on us claims about 1000 lives a year.