I'll expand this and point out "Anti-Gouging Laws" are a form of sanctions and not only make strenuous situations more difficult, but they also create their own markets (among people willing to pay, pay cash, and keep their mouth shut). Lots of government agencies will claim they 'work' and cite a few specific and unusual examples and claim "victory." Pyrrhic, at best. The same is true with governments discussing sanctions.
International sanctions rarely work because of the point made in the title - they create 'black' markets. Russia's oil has sanctions against it? So what. Some country that doesn't care about the West will buy it on the cheap, then resell to nations that support the sanctions but are happy to play intermediary, and eventually it gets back to the West one way or the other. Either as refined product, or by markets elsewhere that undermine the larger market and disrupt supplies.
The communist world had sanctions against many Western goods - but they were always available in communist nations. My father traveled to Russia with a suitcase carrying a few extra cases of Marlboros (he didn't smoke) and a few pairs of Levis. Always good to have the local currency (contraband) ready just in case. A friend who travelled to Argentina 8 years ago, where currency controls were in place, was directed to join a "currency club" where they got a "preferred rate of exchange". The official Argentine rate was so bad, many people set up these "clubs" where they'd exchange at a better rate, knowing they could get the currency out and exchange at better rates outside of Argentina.
There aren't many examples of sanctions working and doing what they're supposed to do. Usually sophisticated nations can find ways out of, or around, sanctions.
In the modern world, the claim was Russia's removal from the SWIFT payment system would cripple them. Someone forgot that the decentralized nature of the internet and cryptocurrencies made the hegemonic controls of a SWIFT system problematic. If you're going to cut someone out of the system - when might YOU be cut out of the system (for any variety of political reasons)? Russia isn't crushing it, economically, but the claims about how poorly it would be doing by now were clearly overblown and based on a poor understanding of modern economic interactions.
