Luckily Russia prints rubles so problem solved!

(Russia has US$ in overseas accounts - but they've been frozen.)

That's right. Their other option is to offer increased interest on bonds in an attempt to borrow money, and that will put further pressure on the currency. In other words, if Russia wants to borrow money and nobody wants to lend it to them, their only option is to offer a high interest rate, but to meet that rate, they have to print more money. Again, it's a death spiral for a currency.

The catch here is that those interest rates on currency bonds (or the bonds) are almost always in USD. So Russia is screwed. Countries that issue bonds in USD can easily crash if their currency collapses. This is why the US is in this position of being able to borrow as much is it likes, because it's the reserve currency.

South American countries aren't borrowing in their own currencies. They're borrowing in USD. If their currencies collapse, their debt is non payable and they default. This is what's happening all over the world.

Again, the whole system is based on a hollow currency, the USD. There is no value backing all this up. It's all make believe. How can a house that was worth 50K 20 years ago now be worth 2 million?