Summary

We handle this topic differently than any other in the report because, while there was fairly strong support for including this topic (79% of the public said the topic was important), no measure related to this topic received more than 61% support from the public. The board vote showed even less support for the individual measures. The apparent reason is that national security is more difficult to measure than other topics. For example, the military defense aspect of national security depends on factors such as the effectiveness of our weapons systems and military, our military and diplomatic strategies, and the strengths and strategies of other countries, all of which are difficult to quantify.

In other sections of the project where we did not trust particular measures, we could simply focus on the best available measures under that topic. The situation is different here because we have concerns about all the potential measures, individually and collectively. It is not a question of the credibility of the data sources, but whether it is even possible to measure national security well. For that reason, we have chosen to discuss the topic in a different way. Rather than report figures in this section and draw conclusions from trends that have modest support from the board and the public, we discuss some of the measures that had the most support. We also explain how national security is related to topics that we report in other sections, especially the economy, environment, citizenship and democracy, and violence.

Measures with the most support

Three measures received majority, but not supermajority, support from the board: interest among young people in serving in the military, the military expenditure of North Atlantic Treaty Organization (NATO) allied countries, and bipartisan congressional support for major defense bills. We discuss each briefly below. The figures underlying this discussion can be found in the Data Notes. Again, we do not include the figures in this section because all of the measures had limited support and we do not believe these measures provide a sufficiently compelling picture of our national security.

  • Interest among young people in serving in the military. We found three measures of this: stated plans for military service among high school students; the number of people applying for military service; and the number who applied, were deemed eligible, and made it through initial training (called “accessions”). The percentage of high schoolers showing interest has been fairly stable, fluctuating in the 10‒12% range since 1994. However, the number of applications has been steadily declining. (Accessions have been declining more slowly, possibly because of the caps on the number of new recruits set by Congress.)
  • Military expenditure of North Atlantic Treaty Organization (NATO) allied countries. Our national security depends in part on our relationships with, and strengths of, our allies. NATO has been a key alliance since just after World War II (1949). NATO guidelines recommend that member countries spend at least 2% of GDP on military defense, though many members have fallen short. The percentage of NATO countries reaching this bar has risen in recent years from 10% to almost 30% since 2014.
  • Bipartisan congressional support for major defense bills. Bipartisan support allows the military to plan long term and pursue consistent strategies over time. It provides our allies with confidence that we are committed to our treaties and agreements and sends signals to our adversaries about our resolve and ability to sustain military efforts over time. Congress has generally been more unified in recent years than in the 1990s. Across both parties, Senate support has generally been much higher and less erratic than in the House of Representatives.

Again, we emphasize that the state of our national defense is especially difficult to measure. But, on these three measures, our national security is generally stable or improving. Interest among young people has been steady, and defense spending among our allies is growing, along with support from Congress. The only warning sign seems to be that the initial interest reported by high school seniors is not translating to actual applications to join the armed forces.

Related Topics

National security is closely related to several other topics covered in this report. The economy, in particular, is the basis for our ability to pay soldiers, fund defense-related scientific research, and purchase military equipment and weapons. Moreover, economic partnerships often go hand in hand with military partnerships. Our military allies often rely on us for foreign aid and military equipment that are made possible by our economic power. Also, our control over major global financial institutions gives us power in a wide variety of international negotiations, which are intertwined with our national defense.

The earth’s environment is also central to our national defense, though in more indirect ways. Climate change creates instability, both at home and abroad. For example, as greenhouse gas emissions continue leading the earth’s temperature to rise, large migrations of people seeking healthier climates across national boundaries are likely to follow. Climate change may also lead to scarcity in basic resources, such as food, drinkable water, and shelter. All of these forces can destabilize governments and lead to armed conflict as countries try to provide the basic needs of their citizens.

For the purposes of both deterring adversaries and responding to their threats, it is also important that our citizens support the systems and institutions responsible for protecting us. Declining belief in democracy and distrust in the federal government along with rising political polarization undermine that support over time and degrade our ability to prevent and respond to threats.

Our success on the above dimensions, as reported in the other sections, has been mixed. While our economy remains strong, we have fallen behind China, which now has the world’s largest economy, in GDP. Belief in democracy, while still strong, has been waning. Finally, partly because of our own limited success with greenhouse gas emissions, we have provided limited global leadership on the topic, which will ultimately be necessary to stem this global problem. (See the Economy, Citizenship and Democracy, Environment, and Trust sections.)