The biggest problems...

I would say the big ones are:

- global warming

- world population increase

- the new aggressive China / new cold war / possible hot war

- massive third world migration into Europe (I know this will be controversial, but if the trends of the last few decades continue it is hard to see it ending well).

When we look back in 50 years these will be the big things, and hardly anyone will remark on either Covid or Brexit.

If global warming is to be taken seriously at some point China will have to come under pressure to stop building new coal fired power stations. They will not react well to that pressure I should think.

There is a possible scenario in which global warming causes even more migration from Africa to Europe, creating a backlash of extreme ugliness. Once these things start to slide, they can get bad fast.

If we don’t sort climate change and environmental degradation sharpish none of the other things will matter very much. 
however my guess is that we will continue to be distracted by those other things until the world’s natural systems crash and we’re all fvcked. 

World population will I think turn out to be less of an issue. Already signs of slowing growth and peak may come quite soon and then decline slightly. May also have a knock on effect on migration.

Black swan event- China in its current guise will end this decade. History repeating itself, innit.

And there will be more viruses. This one isn’t the big one.

Re third-wold immigration - Douglas Murray is right. We have had too much too quickly and have totally failed to integrate them into our society. We haven't even tried that hard to do so really. We need to be a lot more selective about immigration. 

Thug and Guy are not going to like this blatant RACISM.  You say "them" like they are different.  You should name them all individually to show you are not RACIST!  Shame on you. 

Environmental degradation/climate change/ecosystem collapse/rising sea levels will spark mass migration, famine, and food and water scarcity on a mass scale. 

Within 20 years this will be the key driver for EVERYTHING. 

Scylla, the rate of change in world population, CO2 levels, resource depletion etc is so incredibly high that it must end pretty soon, and it is going to be ugly when it does.

So far migration policy has been about how many of the hundreds of millions wanting to move from the third world to Europe will make it each year. But if Europeans start to feel deeply threatened the response may become much more brutal.

Scylla, the rate of change in world population, CO2 levels, resource depletion etc is so incredibly high that it must end pretty soon, and it is going to be ugly when it does.

So far migration policy has been about how many of the hundreds of millions wanting to move from the third world to Europe will make it each year. But if Europeans start to feel deeply threatened the response may become much more brutal.

For example, entire nations will disappear. Maldive, many of the pacific islands, Bangladesh, large portions of other will also be under water or become uninhabitable. Myanmar, Siberia anything build on it in the permafrost zones.  

We have no plan on what will be done with the hundreds of millions of people who will simply be environmentally displaced in the coming years. 

That refugee flow triggered by the Syrian civil war is just a very small example of what the whole world will look like. 

Immigration has been a constant in Europe since the end of ww2 and although it constantly provokes opposition no-one's gone to war because of it.  The fact you think this is a recent issue pretty much proves it.  Besides, the truth is its our gain and their loss - we cream off the most motivated and dynamic individuals from these countries, as well as a good percentage of their professionals and people who would otherwise be leaders in their countries. 

Population expansion is fine, the rate is slowing as the world becomes more prosperous, and we have capacity for billions more people.  Besides, what exactly are you going to do about it apart from accommodate it? 

Climate Change and the likely cold/hot war with China are big ones.  Brexit will be one of those things that become part of a story and it depends what's at the end of that story.  I expect it will be maybe Anschluss with Austria type of historical significance 

World population increase is massive issue, not helped by the fact that it is such a politically and religiously sensitive subject to discuss openly in public. It seems very much the case that two of the world's leading religions are seeking to win in the numbers game and the countries where these are in particular competition with each other are projected to have some of the most startling projected population rises in the next thirty years. By way of example by 2050, Nigeria is projected to be the country with the world's third largest populatiom (behind India and China)!

Warren, large scale peaceful migration has not really been "a constant".

Large scale migration historically has usually been as a result of military conquest. E.g. migration of white people into America, Australia etc. Before that the Vikings, Anglo Saxons etc came to the UK not as peaceful settlers but by force.

What is quite novel, over the last few decades, is peaceful migration on a massive scale. This is a feature of the west. It is not allowed in places like China, Japan, Korea, or indeed most of Africa.

Can it continue? The Muslim population for example in the UK keeps doubling every 13 years, and has been doing so for about half a century. No such rapid exponential increase can continue I think, but what will make it end?

As for the idea we have room for billions more... only if we accept massive global warming and enormous environmental damage.

People have been saying (usually - but not always - snobs and racists) that world population increase is a huge insurmountable problem for hundreds of years, they are always proved wrong.

Population growth is an exponential problem as in the scale of the problem is magnified generation to generation.  

The real problem which most won’t touch on is global inequality.  A very small percentage of people live a life of absolute luxury.. that includes everyone posting on this board.. we all have a roof over our heads, food on the table, access to electricity, internet and a computer, education etc etc

The vast majority of people on this planet  may as well be living in the 1800s. 

There are hundreds of thousands of people globally who die of poverty, malnutrition, basic and very curable diseases. If everyone on earth wanted to live as we each live then we need something like the equivalent of 5 earths to do it. 

Equally as soon as poor people have more education, women are economically valued and childhood mortality rates drop... birth rates also drop significantly. 

The earth can support the current world population... if the resources were far better managed and distributed. 

We have the ability to feed the humans on the earth.. we do not have the resources however for them all to drive cars, fly around the world being tourists or even for them all to own a refrigerator.

I also agree with others on this thread who have correctly identified the current horrendous damage we are doing to marine ecosystems. 

All life came from the sea.. and most of us still depend on it in one way or another.  Unfortunately since the damage is hidden under the water and cannot be seen by the eye the level of absolute carnage going on in our oceans is being ignored. 
 

we use it as a toxic waste sewer dump. 

Also warren ... I don’t think immigration is a recent phenomenon at all.  

Indeed the Viking raids which almost destroyed England in the time of Alfred the Great were essentially exactly what I’m taking about now. Environmental changes and harsh winters in Scandinavia drove the Vikings to conquer and settle new lands. 

Except then there was only a few thousand of them... and small wooden boats. 

This time there will be millions of them. 

Also. There are already more displaced persons and refugees now than at anytime in human history. Including after WW2 ... the scale of the problem has never been bigger 

Nah.  In the 70's when Earth day started there were massive problems with pollution, resource scarcity and hunger, and all sorts of people predicted the end of the world.  On all the info then it really did look bleak.   That was 3.5 billion people ago and guess what - on any real measure, the current 7.5 billion are far more prosperous, healthy and better off than the 3.5 billion were then.  Technology and social changes have improved life (and life expectancy) dramatically, and there is no real reason to think that won't continue to happen.  Population growth rates have fallen every decade since the war, many of the problems of the first world are actually caused by low or negative growth rates.

Sorry, the fact is the world can accommodate billions more people, and will almost certainly do so while simultaneously raising their standards of living.  Proof?  Because that's exactly what we have been doing, decade after decade after decade.    

Skylla, Obviously people have migrated throughout history.  The point is that migration by minorities into Europe has since WW2 been a constant without anyone having a war.  There is nothing in the current situation that is fundamentally different.  Its an important issue but please don't buy into all that alt-right nonsense about the black/Muslim peril, its poisonous fiction 

Yes. And during that time we have lost 70%+ percent of all other animals on the planet also that time period you are speaking of is less than a second in geological time. As in the time it takes the earth and it’s ecosystems to adapt to or absorb change. 

Humans live in an ecosystem. We are not seperate from it. We rely on insects to pollinate our crops, we rely on healthy soils and rainfall to feed our stock. 

That ecosystem is beginning to hit the limits of its resilience. 

Our particular form of society has really only existed for less and one hundred years (I.e the energy/ fossil fuel society) it has existed in a very specific environmental niche and is highly specialised. 

We will die just as easily from starvation as all those humans before us did. 

Many human civilisations and risen and fallen due to local climate changes.

I’m not buying into any such thing warren.
 

I’m saying the world has no plan or agreed mechanism for where or how the hundreds of millions of displaced people will be accommodated. 

Whether those people are white, brown, yellow or purple is utterly irrelevant to me. 

Just remember people climate change is a geological constant. The entirety of Europe and most of the UK was buried under kilometres of ice in the last ice age some 5,000 years ago. 

climate change will happen. Whether you believe it’s man made or not. And our entire society is built on a very fragile basis in a specific ecological/geological/climate niche that is rapidly passing. 

Our economic, financial and social systems simply do not have the necessary resilience to adapt to the coming change.

There are basically only 2 truly big problems:

1. The relentless ever increasing consumption by the so called developed world;

2. The pig headed refusal of people to pay attention to problems until it’s a bit late in the day. Cf Vuvu - knee it was coming, sat around scratching out balls. Environmental warnings are there but collectively we are doing much the same.