Why all the Illegal Immigrants?

Why are so many first-world countries accepting inordinate numbers of immigrants? It is obvious that the immigrants, legal and illegal, are changing the very fabric of first-world society. Why allow this?

There are many people who would default to the easy answer: political groups allow it because they hope for more votes from the immigrants than they can get from their native citizens. While this isn't wrong, it also doesn't really deal with the heart of the problem: total fertility rate (TFR).

Take Europe, for instance (although America is really no different). Europe's "Christians" are not having children, so they aren't really Christians. Whatever basis in Christian society Europe has had, has been fading since at least the Protestant Reformation, if not earlier. Western society has slowly been moving away from Christianity for centuries, which is how today's political monsters got into power to begin with. But politics isn't the practical problem. TFR is.

Every nation's leaders know this: if immigrants are not brought in, the nation disappears within a century as native citizens die off without having offspring... and the immigrants will move in ANYWAY because the country grows emptier each year. It's not like anyone can stop this. Look at the numbers:

• Median age of Europe is 42.5
• Median age of North Africa is 24.7
• Median age of Africa overall is 19.2

European leaders are hoping that if they bring in immigrants, legal and illegal, while Europe is still somewhat youthful(!), maybe they can assimilate the migrants and enculturate them with European values before the current European population ages out and the REAL deluge of youthful migrants starts.

They're wrong, of course, but you can't blame them for trying. You think waiting until the median European age is 50 or 70 is going to work better?

Hint: it won't.

What else can they do? They can't start an African war. Wars just increases infant mortality. High infant mortality increases TFR. Nobody wants Africa's TFR to go up. Europeans want it to go down. That means they have to reverse centuries of policy in regards to Africa. They have to figure out how to make Africa wealthy, ASAP. 

For centuries, Europe and the US has been deliberately keeping Africa poor and starved so it can mine African mineral resources. Well, that worked just great. Europe got rich on African mineral wealth. But, it turns out that the resulting European wealth depressed European TFR while the resulting African poverty and high infant mortality rates kept Africa's TFR high. 

Nobody thought about that.

So, they sowed to the wind, now they are reaping the whirlwind. Europe got wealthy at Africa's expense, now Africa comes to Europe to get their share of the pie. 

North America is similarly getting its come-uppance, and for similar reasons. America stole literally half of Mexico, we illegally occupied the Philippines for most of the 20th century, and we have been having fewer and fewer children each generation since 1800. As our wealth steadily increased, our TFR steadily dropped. For the last forty years, America's TFR has been below even that of 1930s Depression-era America. We're one of the wealthiest nations on earth, and without immigration, we would essentially disappear within roughly the next century. Already, America's median age is 39, in some states it is nearing 45. That's post-menopausal.

Mars Needs Women, and every country in the world needs immigrants. We're stealing other countries' populations in order to prop up our own. Europe is doing the same. That's why this is happening.