Here is what the Watchtower Society's Reasoning from the Scriptures (1989) ministers' handbook states under the heading of The Last Days on the question of whether it is possible that the sign of Christ's presence and the conclusion of the system of things could display itself in the future.
‘How do you know that some future generation won’t fit the prophecy even better than this one?’
You might reply: ‘That’s an interesting question, and the answer highlights the fact that we really are living in “the last days.” How? Well, part of the sign given by Jesus involves war between nations and kingdoms. But what would happen today if fulfillment of the sign required that we wait until another all-out war were to break out between the superpowers? Such a war would leave few if any survivors. So, you see, God’s purpose that there be survivors indicates that we are now very close to the end of this old system.’
Is the Watchtower's reasoning sound? No. But in all fairness in 1989, when the Reasoning book was originally published, the Cold War was still on and the primary reason the so-called Cold War did not become a hot war is because of the realization of the military doctrine of MAD (Mutual Assured Destruction). The Soviet and America superpowers recognized that the widespread use of high-yield nuclear weapons by both sides would result in the annihilation of the world.
So, in that respect the Watchtower’s viewpoint is correct.
However, the world has changed since 1989. Shortly after the Reasoning book was published the Union of Soviet Socialist Republics (USSR) dissolved. After its defeat in Afghanistan and in the decades since the USSR collapsed, privateers have looted Russia and its military capability significantly diminished. Although still possessing enough weaponry to destroy the world Russia is no longer considered a superpower.
However, the United States is a superpower. And since the end of the Cold War the US has developed its military power far beyond that of its rival. For example, the radar evading stealth bomber is a relatively recent invention. Also, the development of tactical nuclear devices, so-called mini-nukes, greatly increase the likelihood of their use, since they can be used to destroy fleets of ships, airfields and armies in the field without significant collateral damage - so-called. The US even has weapons deployed in outer space.
Since 9-11 the US has for the first time adopted a first strike preemptive warfare policy, which in recent years has been expanded to include a nuclear strike. Although unthinkable to common persons it is an actual war scenario to launch a surprise attack using mini-nukes to take out the nuclear capability of both Russia and China. Presently, though, the most immediate threat of war is an attack on Iran and possibly Pakistan, which would in all likelihood detonate World War Three and give the Anglo-American superpower the pretext to launch wars against Russia and China, especially before China becomes a military superpower in the near future.
Thinking out loud here:
In the book of Acts the holy spirit was used to prevent Paul from entering Asia (modern Turkey) and instead he was directed to preach in Macedonia. The propagation of Christianity within the heart of the Roman Empire has had far reaching consequences; resulting in Christianity being largely connected to European civilization (and the Americas by extension), while the Middle East and Asia have largely been unaffected. Even the work of Jehovah’s Witnesses in modern times has made very little progress in the Middle East and Central Asia.
As it stands presently, the Anglo-American beast is working feverishly to blow up the Middle East and South Asia and create chaos and instability around Russia and China, in what has been dubbed by military policy makers as the Arc of Crisis. It is becoming increasingly more likely by the day that nuclear weapons will be deployed against Iran and Pakistan. The Middle East and Asia certainly appear to be ground zero for the unthinkable. Perhaps it has been divine providence that has kept Jehovah's Witnesses out of this part of the world in modern times.
According to Revelation the ride of the four horsemen will result in one-quarter of the world being laid low in Hades. The first two world wars, food shortages and Spanish Flu pandemic did not even come close to killing a quarter of the population. (A Closer Look at 1914)
However, it is a very real possibility that the inevitable war now looming on the horizon will kill billions. At least that is the intent of the Anglo-American beast now stalking the world.