This is her getting the G-7 finance ministers to agree to a minimum 15% corporate tax. It is easy to sneer at this. Some of the nations involved may not pass it. There are many problems with details, such as whether the tax would be on gross or net income. There are a lot of nations not in on this agreement, including especially large China.
But currently many large corporations are paying zero anywhere, with this reflecting their ability to shift earnings around from nation to nation. Frankly, although I have long been a fan of Janet Yellen's I really did nor expect this plan to go anywhere. There would simply be too much international opposition. But she has pulled off at least the quite significant agreement, supported by President Biden. So I would like to recognize this achievement and applaud it, even if in the end they are unable to push it all the way to through to full implementation.