The United States is the third-largest military with over 1mil active duty personnel, but it also spends the most money and highest percent of GDP on defense spending.
But how well do these numbers match up with Battle Readiness?
The Heritage Foundation’s “2020 Index of U.S. Military Strength," assesses that the United States' forces would be stretched "dangerously thin" if it were to fight more than one war at one time. The Index also assessed the Army, Marine Corps, the Air Force, and the Navy in the areas of "capacity, capability, and readiness." Each of the service branches except for the army were given a "marginal" report, essentially a C grade. Only the Army was given a "Very Strong" report. This does not bode well for the US's ability to compete if forced to fight against more than one military threat (China, Russia, NK, Iran)
Compared to the United States, China's current military has almost no combat experience. "Considerable evidence shows that better-educated soldiers are easier to train, more adept at operating and maintaining sophisticated weapons and platforms, and more capable of executing complex tasks." While China commands one of the most high-tech arsenals in the world, it remains to be seen if they are able to utilize it effectively. However, in the past 5 years, China has bolstered military diplomacy with its allies, particularly in joint-military exercises. Between 2003 and 2014, China participated in a total of 130 military exercises, an amount nearly matched by the 124 exercises China joined in 2016 alone. While these exercises cannot take the place of combat experiences, they definitely improve the battle-readiness of China's military.