How are they able to generate the income? Through the services YouTube provides from the US. How is YouTube able to provide those services? Because the US government creates infrastructure to enable it. How is that infrastructure paid for? Taxes. Hence they tax the income.
If you live in the EU and work for Google, you probably actually work for Google's EU-based subsidiary. There's no US-based company involved in the relationship. It's confusing because the company treats all the subsidiaries as one whole, while the law treats the subsidiaries as their own entities.
AFAIK this misses the point. If a EU citizen is contracted by a US company, but living in the EU they are not subject to US income tax at all, but only to their own state's - and also this might not be legal if the US corp has a EU subsidiary. (If they live in the US they are taxed by the US first and their home country second, but taxes paid in the US are being deducted from the taxes they have to pay in their home country. And, if they are contracted with a EU based subsidiary then they are taxed in the EU only, obviously.)
> If they live in the US they are taxed by the US first and their home country second
That's not universally true. My home country doesn't require any income taxes from me since I neither work nor live there. AFAIK the US is quite unique in that regard that they require their citizens to pay taxes no matter where they are working or living.
> the government creates infrastructure to enable it.
Hearty laugh.
Yes, to a degree, but at the current time (and for a good long time) the US government does not even pretend to try. Tell me a significant infrastructure package since the interstates.
Many relevant infrastructure are created by telecom companies, should we owe taxes to those too?
How are they able to generate the income? Through the services YouTube provides from the US. How is YouTube able to provide those services? Because the US government creates infrastructure to enable it. How is that infrastructure paid for? Taxes. Hence they tax the income.