If you get married and have kids in the west, you are looking at losing half your assets and over half your income in the event of divorce. You will also pay a high tax burden. If you cohabit in the west, you are only on the hook for child support - much more palatable but still expensive, due to the unjustifiable assumption that you would spend a lot on your kids, rather than raise them frugally, even if you are a high-earner. By contrast, if you knock up 10 women in the 2nd or 3rd world, you probably won't be liable for any child support at all. Even if you are, or just are a nice guy, it'll cost you like $50 a month for each kid to live in relative luxury. If you marry one (or 4 in certain regions) your divorce liability is not particulary high. You could probably get them to settle for 20k or so and they'd become fairly well-off overnight. Add to this the fact that taxes are in the 15-20% range in much of the world, compared to 30-60% in the west. So, having 1 kid and one wife in the west can potentially take 70-80% of your gross income if things go wrong. Whereas if you propagate the species with non-western women abroad, you lose less than 1% per kid and maybe 5-10% per divorce if you are generous. You could have 20-30 kids and several wives for the same price as 1 kid and 1 wife in the west. Basically the tax, alimony, divorce and child support laws in the west give strong financial encouragement to the dying out of western populations and the migration south or east of all affluent males (and some females) in those countries. It incentivises the fiscal bankruptcy and population decline of the west.