Why does it say 0 for the US? You have Thanksgiving, Christmas, 4th of July and more? Are they unpaid days off?

Depends on the company. The US maintains no requirements, federal holidays are a suggestion, not a mandate.

A few states inside the US upgrade federal holidays to state holidays to required paid time off. Most don't.

In the US paid holidays are a corporate "tradition" more than a regulated common good.

Even US federal employee holidays vary between agencies and branches of government.

I think they're technically not federally mandated. Businesses can be open on Christmas at their discretion and require workers to come in.

It depends on the job and is not mandated to be paid, or even given off.

Holidays are on top of vacations so they shouldn't be counted .

The rest of the world seems to believe that if the government doesn't mandate it, it doesn't happen.

Because it gets more attention if they ignore reality and treat a lack of a federal mandate as meaningful information.