Ramanan criticizes the MMT claim that imports are benefit in real terms and trade deficits don't matter as long as other countries desire to save in the importer's currency, because floating rates ensure market clearing and a currency sovereign is not constrained operationally in its own currency.
Read it at The Case of Concerted Action — Post Keynesian Ideas For A Crisis That Conventional Remedies Cannot Resolve
The Monetary Economics Of Sovereign Government Rating
by Ramanan
Ramanan has a comments section at The Case of Concerted Action, where I expect one can count on his responding to reasonable criticism. Comments welcome here, of course.