Editor’s Note: Julian Zelizer is a history and public affairs professor at Princeton University and the author of “The Fierce Urgency of Now: Lyndon Johnson, Congress, and the Battle for the Great Society.” He’s also the co-host of the “Politics & Polls” podcast. The opinions expressed in this commentary are his own.

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Julian Zelizer: US policymakers believed in collective security and military restraint in '90s

Unfortunately, rising threat of terrorism undercut optimism in diplomacy, he says

CNN  — 

The early 1990s offer an important reminder to the way that US policymakers – for a time – believed in collective security, diplomacy, international alliances and military restraint.

As the Cold War came to a close, President George H.W. Bush and a large number of world leaders deeply valued the benefits that working through international institutions could offer to pursue national security objectives.

Unfortunately, that commitment, born out of the stunning achievements of the Western alliance in World War II and the Cold War, is at risk in 2017 as the United States and other foreign leaders have moved way from these goals.

As the Soviet Union crumbled, Americans lived through events as dramatic as anything that has taken place in recent years. The defining tension that had shaped the world since the mid-1940s – the conflict between the Soviet Union and the United States, both armed with nuclear weapons capable of destroying the world – abruptly ended.

We watched this take place on the 24-hour news cycle. President Ronald Reagan and Soviet leader Mikhail Gorbachev had brokered a historic nuclear arms agreement in 1987 that launched the new era. As the Kremlin backed away from its stranglehold on satellite states in Eastern Europe, revolutions swept through the region, some peaceful and others violent, all of which brought to an end to the Soviet Union.

While these destabilizing changes occurred, Bush understood that a militaristic attitude was not always in America’s best interest, a knowledge gained from having been a congressman, US ambassador to the United Nations, envoy to China, CIA director and vice president.

With revolution sweeping through Eastern Europe, Bush famously restrained from saying too much so that the United States did not look as if it were boasting or trigger a backlash by appearing to intervene. When the Berlin Wall fell and Germany reunified, he worked hard to obtain the support of Gorbachev, whose fellow countrymen were extraordinarily uneasy with this development. The United States and the Russians signed START I and START II, which resulted in steep reductions in nuclear weapons.

After Iraqi leader Saddam Hussein invaded Kuwait, Bush and his advisers put together an impressive international alliance to push back against this aggression.

In this case, Bush and US allies did use military force – but the President insisted on adhering to the limited objective of having Hussein pull back his forces and resisted pressure for regime change in Iraq.

While neoconservatives would see this as a massive error, years later the decision looked much wiser when the United States ended up in a terrible quagmire after taking down Hussein and his regime in 2003. The elder Bush’s kind of limited, alliance-based warfare would remain an important model for his successor, Bill Clinton.

The promise of peaceful change was strong in what Bush called the “New World Order.” When the South African government released Nelson Mandela from prison and apartheid came to an end without war in the early ’90s, the possibilities of revolution were tangible to parties involved in conflicts around the globe. Around the same time – as the recent award-winning play “Oslo” has depicted – the Israelis and Palestinians also reached a historic accord over territory and security that still constitutes one of the most important breakthroughs in the region.

There were many diplomatic failures during this period that should not be forgotten.

Bush’s decision to bring down Panama’s Manuel Noriega remains a controversial example of the administration still practicing an older style of intervention in Latin America, while Clinton’s hesitance to use force to stop the genocide in Rwanda reveals the costs of the United States deciding to stay out of the fray.

Unfortunately, this moment seems like a different era. The rising threat of terrorism, which culminated with 9/11, undercut the optimism in diplomacy and gave way to new generation of US leaders, including Bush’s son, who leaned toward proactive and unilateral military action.

Conservative politicians regularly blasted the value of international alliances, complaining they did not put America first. The promise of diplomacy waned. In the Middle East, the walls separating the Israelis and Palestinians became literal. Rather than Gorbachev, the Russians are now led by someone who is intent on destabilizing our democracy and who has embarked on expansionist territorial ambitions.

President Barack Obama attempted to make negotiation a preferred form of international relations, as expressed with the Iran nuclear agreement, but support for his methods was undercut by the deterioration in Syria and the election of a president, Donald Trump, whose bellicose rhetoric offered little hope for any kind of new world order to emerge.

The state of diplomacy has been made clear as key positions in the State Department remain unstaffed and the proposed budget cuts for this key institution of government are draconian.

Trump, who spent much of his campaign blasting NATO, has continued to send mixed signals about where he stands on this vital alliance all the while continuing to take a weak stand toward Russian aggression.

We need to look back to the hope of the early 1990s as a rare moment when diplomacy, international alliances, collective action and military restraint were the dominant principles of US foreign policy.

The moment didn’t last long, but it was crucial to helping the world transition from the Cold War to the new era without war.

Program note: Explore the “The Nineties” on CNN at 9 p.m. Sundays ET/PT.