You have to go beyond war and connect the dots to see what's happening. That is,
There has been a multi-fold increase in armaments production and deployment worldwide, with a greater emphasis on long-range weapons of mass destruction, automated delivery systems, and anti-personnel devices.
Increasing numbers of casualties involve unarmed civilians, and many children and the elderly. Many die because of disease and hunger brought about by conflict.
Many conflicts involve proxy wars, i.e., using weak countries as battlefields, and they include combinations of dirty tricks leading to military intervention, destabilization, military and trade deals, etc.
Ecosystems have been falling apart globally, from fresh water availability to aquatic resource depletion. The main causes are pollution, growing economies, and effects of abnormal natural disasters such as extended periods of cold, droughts, and precipitation leading to floods.
Since 2000, scientists have detected over fifty positive feedback loops driven by global warming and part of climate change. Groups ranging from military forces to insurers to multinational banks have issued reports warning personnel and clients about this long-term crisis.
Since 2010, the IEA has reported that global conventional oil production started peaking in 2006. Eight indicators show that total oil production per capita peaked back in 1979. Various industrial data show that oil, in terms of energy density and petrochemicals, has been the lifeblood of global industrialization and mechanized agriculture since the end of WW2, and more of it will be needed to meet not only basic needs of a world population but even a growing global middle class. The equivalent in terms of total resources and energy needed to sustain growth in the long term is equivalent to around four more earths.
In order to maintain and increase oil production, the industry had to accumulate over 2.5 trillion dollars in debt, and can only pay for that and borrow more if oil prices go up to at least $100 a barrel. But the world can't sustain that cost, which is why it experience weak growth during the past decade.
Some of the groups that issued reports on climate change, such as the U.S. military and Lloyds of London, also issued reports about peak oil and the threat of a resource crunch. That is, because of gravity and physical limitations in the biosphere, then there will naturally be a peak in resource availability, from oil to minerals, and as part of diminishing returns.
Finally, financial debt and speculation are icing on the cake. The level of credit worldwide has been soaring for years, with the notional value of unregulated derivatives alone estimated by one expert at over one quadrillion dollars. "Only" one trillion dollars of that, through subprime lending in the states, was enough to bring the world to its knees in 2008, and there's more where that came from.
From there, connect the dots:
Some scientists argue that a global nuclear war isn't even necessary, as even limited or tactical nuclear war can have unusual effects on climate when coupled with soaring CO2 ppm (over 400, the highest in hundreds of thousands of years, where natural cycles lead to a peak of only 300 ppm).
With oil, globalization, and various wants of the middle class (like accessing forums like this using fancy devices and highly complex infrastructure), extensive supply chains spanning many regions and thousands of miles are needed. For example, most don't know that the very devices they use to go online and become excited over war have no idea that those devices involve dozens of countries and services, with only a few days' worth of raw materials, good in progress, and finished goods available in every town, city, and supply hub worldwide to keep inventory costs down. We've seen what limited natural disasters or wars can do to that system, such as massive floods that wipe out a third of hard drives available or temporarily closure of trade routes for oil. Imagine what full scale war can do.
There's recent news that the current pandemic may have involved tweaking viruses as part of gain of function research by multiple countries (including China and the U.S.), with funding from gov't agencies and private corporations. The viruses also spread through increased vectors due to combinations of the effects of industrialization (from urban congestion to more travel to clearing of wilderness areas for housing and business), natural disasters (extended droughts and floods), pollution (in the water, in the air), resource crunches and breakdowns (in utilities due to natural disasters, urban congestion), etc.
In short, connecting the dots means showing how one or more problems given above amplify other problems.