The budget agreement finally reached by Congress last Friday provides around $700 billion for national defense in fiscal years 2018 and 2019, an allocation in line with President Trump's 2019 budget request, released by the OMB this morning.

Here's what you need to know about that spending:

1. The defense budget is big, about the same size as the entire Swiss economy. It consumes over half of discretionary spending, though only about 16 percent of the total budget (including Social Security, Medicare and other programs). But the expenditure is not unreasonable: Not only is the U.S. military the finest fighting force in the world, with over 2 million men and women on active duty or in the National Guard or Reserves, it also has components that are basically a health care company, a global supply chain outfit, and a sizable retail operation.
2. While it's true that the United States spends more on defense than the next eight countries combined, global leadership — and the benefits that accrue to the American people — does not come cheap. U.S. military might ensures that the other expressions of U.S. power (diplomatic, economic, social) operate from a position of strength. As China and Russia challenge this order by violating the territorial integrity of neighboring countries, meddling in foreign elections, and attempting to limit freedom of navigation, it's more important than ever to maintain our edge.
3. The unpredictability in defense budgets, caused by erratic Congressional dealmaking, is harmful in and of itself. The new deal will bring some badly needed stability and a substantial funding increase, but even still it will not achieve the force structure growth the President promised on the campaign trail — nor should it, given the many other worthy and pressing priorities facing the federal government, and the expected decrease in federal revenue that will result from the recent tax cuts.

The bottom line: With good stewardship, these resources can ensure the U.S. has the military capability and readiness to underwrite global leadership.

Go deeper: More defense budget analysis from CNAS.

Susanna V. Blume, a former Pentagon staffer, is a fellow at the Center for a New American Security.