Quora Question: How Have National Security Threats Changed in 40 Years?

Afghan security forces
Afghan security forces patrol during ongoing clashes with ISIS fighters, Kot District, eastern Nangarhar province, July 26. ISIS has established a presence in eastern Afghanistan. NOORULLAH SHIRZADA/AFP/Getty

Quora Questions are part of a partnership between Newsweek and Quora, through which we'll be posting relevant and interesting answers from Quora contributors throughout the week. Read more about the partnership here.

Answer from Arnold Punaro, author, Vietnam war veteran, USMC, former staff director of SASC:

Forty years ago we were primarily focused on the threat of the Soviet Union and Warsaw Pact nations who challenged the US and NATO. The Soviets had a massive nuclear force that could reach the US from abroad and a massive conventional force that had the potential to overrun the NATO defenses in Europe very quickly. We were also worried about China and their military capabilities, along with North Korea and the potential for renewed conflict on the Korean peninsula. We relied primarily on deterrence both in the nuclear area and in the conventional area to keep these threats from becoming outright hostilities.

After the fall of the Berlin Wall and the breakup of the Soviet Union, our defense leaders recommended reducing the size of our active military and many of our major weapons systems that were there to combat the Soviet threat. After both the Soviet Union and the U.S. agreed to cut our nuclear forces down, for many years we did not have to worry about peer competitors or arms races. But today Russia and China are beginning to catch up technologically with us, and the potential for peer competition is back. We had significant technological advantages during most of the Cold War, but in a number of key areas our lead has diminished, and in some areas we’ve even fallen behind, so we need to refocus on restoring those advantages.

I agree with our defense leaders today that we face five major threats: Russia, China, Iran, North Korea and global terrorism. Russia has become more aggressive on the international front, and China is pushing their advantages in the South China Sea. Though we have a nuclear deal with Iran, they are pushing the limits in terms of bad behavior. And North Korea now finally possesses nuclear weapons, and their leader is as unstable and unpredictable as ever. The rise of global terrorism also provides a challenge for the U.S.: In the past we could deter countries like Russia and China with our military might, but with a terrorist group that has no borders, no capitals, no economic markets and no citizens, deterrence as a strategy is useless.

How have national security threats changed in the last 40 years? originally appeared on Quora—the knowledge-sharing network where compelling questions are answered by people with unique insights. You can follow Quora on Twitter, Facebook, and Google+. More questions:

Editor's Pick