MMT centers around the notion that the economy in general, and money in particular, should be the creatures of the State. It’s not a new idea – the meme has been around in one form or another since at least the days of Marx. MMT basically posits that the wise and incorruptible solons in government should create as much currency as they think is needed, spend it in areas they like, and solve any problems that occur with more laws and regulations.
https://www.caseyresearch.com/doug-casey-on-modern-monetary-theory/