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.
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.