The deadliest conflict in human history began exactly 80 years ago. On Sept. 1, 1939, Nazi Germany invaded Poland. Britain and France came to Poland’s defense, and suddenly World War II was underway. Estimates of civilian and military deaths in the war go as high as 85 million.

Could there be a World War III?

While there have been many wars since World War II ended in 1945, the major powers have never launched all-out war against each other since then. Leaders know if they ever turned to nuclear weapons, the nightmarish death toll would make World War II look like a minor skirmish.

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But no one can predict the future or say that World War III would be impossible. Regional wars and crises have the potential to explode, with actions and unanticipated reactions leading events to spin out of control.

There are a number of global hotspots today.

China now seems determined to try to dominate Asia and create its own sphere of influence, while subjugating its own citizens to tyrannical rule, as we see with its efforts to crush demonstrators fighting for more freedom in Hong Kong.

Russian President Vladimir Putin has mourned the breakup of the old Soviet Union. He has rebuilt Russia’s armed forces and started and stopped frozen conflicts in Ukraine, Moldova and Georgia – all formerly part of the Soviet Union. With NATO and Russian forces now probing each other’s air and naval spaces on a daily basis – and with both sides now likely arming with dangerous missile platforms that were once banned under an expired treaty – we don’t know what could happen if things get out of control.

The anniversary of the start of World War II should remind us of the sacrifices and heroism of the Greatest Generation. And it should serve as a reminder to leaders of all nations that the world remains a very dangerous place, where a spark can turn into a deadly conflagration in an instant.

Of course, we can’t forget about North Korea. President Trump and North Korean leader Kim Jong Un have held three historic meetings. But the North has not wound down its nuclear weapons and missile programs, and has now even gone back to testing short-range missiles. Kim has threatened by the end of the year to embrace a “new way” that could mean a return to nuclear weapons or intercontinental ballistic missile testing, setting the stage for another round of rising tensions on the Korean Peninsula.

Unfortunately, the possibility of armed conflict involving the U.S. has not dissipated. In fact, in the years to come, I would argue there are three specific flashpoints that must be watched carefully in order to ensure that World War III never becomes a reality.

Cyberspace: World War III could very well begin in a domain that never existed during World War II.

No treaties or international bodies police the conduct of nations on the Internet. So cyberspace has become like a 21 century Wild West frontier town, with no rules to keep the gunslingers from battling it out for supremacy. In cyberspace hackers are working to steal intelligence, intellectual property and military technology. This could escalate into attacks that would disable a nation’s power grid, plunging it into darkness for weeks or even months, or other actions that would cause catastrophic damage.

We should never discount the possibility that a rogue nation or terrorist group could go too far or make a tragic mistake, accidentally employing a cyberweapon that leads to the death of innocent civilians or severe damage to the global economy.

That could cause the accidental or intended target to strike back with military force. In that case, the stage could be set for the very first cyberwar in history that could draw in nations from around the globe with terrible consequences in the physical world.

A U.S.-China Trade War Becomes a Shooting War: Imagine if the world’s two largest economies – worth around $32 trillion combined – started shooting at each other. Think that’s impossible? History tells us it’s entirely possible, and the spark could be today’s current trade war.

China has already declared its economic performance a “core interest” – meaning that Beijing would fight to ensure its continued success. If the U.S.-China trade war escalates to the point that Chinese leaders believe a recession is imminent, Beijing could gamble that a show of military force is necessary.

In that case, China could take an aggressive action in the South China Sea, demand to take control of Taiwan, or even an attack critical commercial Earth-orbiting satellites vital to our economy and military.

A U.S. counter-response – with China retaliating – could spark a war in Asia that would surely draw in most U.S. allies in the region and launch a global crisis of epic proportions.

A Korea Crisis: Imagine a situation where the current trend lines continue. Kim Jong Un could decide to break his verbal promise to President Trump and test the ultimate weapon – an ICBM with a fully developed warhead that drops down into the atmosphere and survives reentry.

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A test like this would prove once and for all that not only do Kim’s missiles have the range, but they can now deliver a nuclear payload to the United States. The stage would be set for a showdown, perhaps prompting President Trump to order an attack and end Kim’s weapons of mass destruction programs once and for all.

Should the U.S. and North Korea plunge into a nuclear conflict, millions of people could be killed, as I wrote about previously in a Fox News op-ed.

Other regional conflicts around the world could, of course, escalate out of control as well. That’s because global peace is a fragile commodity. One wrong move could start a chain reaction that – in the worst-case scenario – could culminate in the chain reaction of nuclear bombs.

Some people who lived through the horrible war that began exactly 80 years ago are still alive today. The rest of us have parents, grandparents or great-grandparents who lived through those terrible days or who died in World War II.

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The anniversary of the start of World War II should remind us of the sacrifices and heroism of the Greatest Generation. And it should serve as a reminder to leaders of all nations that the world remains a very dangerous place, where a spark can turn into a deadly conflagration in an instant.

Let us hope and pray that World War III remains just a nightmare that never becomes a reality, and that future generations do not have to mark the anniversary of the start of such a conflict.

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