Ms. Koike makes a good point. The international law is based on a system of promises and threats. Most of the time, nobody deviates from law. However, when there is a violation of the law, there should be a tangible reaction with material implications for those who violated the law. Otherwise, the whole system of relations is worthless.
Just think about the case when criminals are not punished: the lack of punishment invites greater crimes.
It seems we're going to see a war of attrition before political leaders are going to start looking for a real solution to the crisis. In this sense, it is similar to the Cold War when one party was waiting to another party to cave in. This time however it is not clear how Russia is going to win in the end. It seems that all fundamentals (economic, military, political) are not in Russia's favor.
Long term you might be right but Putin, if smart could settle for the Balkanization of the Ukraine into semi autonomous regions that are really led by fear of the little green men you see with sub machine guns at each occupied town, supplemented with the assassination of pro Ukrainian politicians in this area. The USA's current President nor Angela Merkel would not likely deploy enough meaningful threats to change the mind of a cruel, bloody but crafty former KGB operative.
My hope though is that this reenergizes NATO to bring the European forces up to where they should be, and to diversify their energy sources as quickly as possible (by fracking, importing nat gas from Algeria, Qatar and the USA as well as reminding all of the other neighbors of Russia, like Kazakhstan, Azerbaijan and Georgia to rearm and be extremely wary of similar "spontaneous" outbreaks of discontented Russian nationals
Economic sanctions are not going to work over night. Isolation is going to wear down the Russian economy, like it did with the Soviet economy. Some sanctions however can have effects even in the short run. For example, a collapse of oil prices can finish Putin's regime in Russia.
Open societies have not always needed defending in the determined way that they do today. But the tide turned against them after the 2008 global financial crisis, and, more than a decade later, the threat posed by authoritarian nationalism continues to rise.