The U.S. conventional force posture on Europe is on the decline. This has been traditionally considered the core element of deterrence. The absence of a major war on U.S. soil since 1945 would presumably be considered solid empirical evidence in support of the policy of forward deployment of conventional forces.
The above chart is a draft & preview of the forthcoming update of my dataset, thanks to research support from Kien Deshpande, a student at Stanford University.
Some eagle-eyed readers will ask if this data counts U.S. troops in Poland. According the government of Poland, they are proud host to 10,000 American soldiers. And the U.S. Army says that its V Corps is now headquartered in Poland, following orders from President Biden in 2022. Yet the Defense department’s office in charge of publishing quarterly troop deployment data (DMDC) reports just 216 American soldiers last year. That’s the challenge in compiling a dataset based on government reports: we have to constantly revise the baseline data with other firsthand evidence.
"The absence of a major war on U.S. soil since 1945 would presumably be considered solid empirical evidence in support of the policy of forward deployment of conventional forces."
IIRC, there's been no major war on U.S. soil since 1865 and no foreign war since about 1815, long before the forward deployment of conventional forces, so the empirical evidence doesn't seem that "solid." :-)