@snood,
You make some good points. The EU and the US have already sanctioned Russia:
Here's from Wikipedia:
European Union-countries that have collectively introduced sanctions
International sanctions have been imposed during the Russo-Ukrainian War by a large number of countries against Russia and Crimea following the Russian invasion of Ukraine, which began in late February 2014. The sanctions were imposed by the United States, the European Union (EU) and other countries and international organisations against individuals, businesses and officials from Russia and Ukraine.[1] Russia responded with sanctions against a number of countries, including a total ban on food imports from Australia, Canada, Norway, the United States and the European Union.
The sanctions by the European Union and United States continue to be in effect as of February 2022. [2][3] In January 2022, the EU announced the latest extension of sanctions until 31 July 2022.[4]
The sanctions contributed to the collapse of the Russian ruble and the Russian financial crisis.[5] They also caused economic damage to a number of EU countries, with total losses estimated at €100 billion (as of 2015).[6] As of 2014, Russia's Finance Minister announced that the sanctions had cost Russia $40 billion, with another $100 billion loss in 2014 taken due to the decrease in the price of oil the same year driven by the 2010s oil glut.[7] Following the latest sanctions imposed in August 2018, economic losses incurred by Russia amount to some 0.5–1.5% of foregone GDP growth.
In addition to the sanctions, Russian President Vladimir Putin has accused the United States of conspiring with Saudi Arabia to intentionally weaken the Russian economy by decreasing the price of oil.[8] By mid-2016, Russia had lost an estimated $170 billion due to financial sanctions, with another $400 billion in lost revenues from oil and gas.[9]
According to Ukrainian officials,[a] the sanctions forced Russia to change its approach towards Ukraine and undermined the Russian military advances in the region.[10][11] Representatives of these countries say that they will lift sanctions against Russia only after Moscow fulfils the Minsk II agreements.
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As to their effectiveness, there's an article here:
https://www.atlanticcouncil.org/in-depth-research-reports/report/the-impact-of-western-sanctions-on-russia/
No country wants to send their people overseas in a war which doesn't involve them, nor should they. This is not our/your war and there shouldn't be any need for a war. At the moment, it's just a threat. Is he testing our resolve and commitment? The list of proposed sanctions is aimed, I think, at making Putin consider exactly what he's doing. There's not been this strong a reaction to his actions before. I hope he reconsiders his dangerous and stupid position. Re your point about imposing these sanctions to prevent him from invading Ukraine, I don't think anyone wants to provoke him into doing something rash.