The Janus Capital fund manager argued in his letter that the Fed’s policy of keeping interest rates low for years has failed to significantly boost the economy. He also noted that the central bank and its model for the economy have become “increasingly addled.” Gross writes in the letter, “Why after several decades of 0% rates has the Japanese economy failed to respond? Why has the U.S. only averaged 2% real growth since the end of the Great Recession? How’s it workin’ for ya?”

It’s an odd time for Gross to be criticizing the Fed for low interest rates, though this is far from his first time of doing so. The U.S. central bank decided in December to raise interest rates for the first time in nine years, despite some opposition on Wall Street. Gross seems to be taking issue with the fact that the Fed decided to keep interest rates steady at its January meeting. He also seems to think the Fed signaled that it wouldn’t raise interest rates again for a while, but the Fed didn’t make a clear statement about what it would do next. Gross also took issue with the European Central Bank, which said it would be willing to push rates in Europe further into negative territory.

Gross’ argument focuses on the so-called wealth effect. He says that while low interest rates have boosted the stock market and other financial assets, those gains have failed to spur consumer spending or otherwise spread to the real economy. As a result, the Fed shouldn’t be worried that the market has mostly headed south since it raised interest rates in December. If rising markets didn’t boost spending growth, then falling markets shouldn’t hurt either.

The problem with this logic is that the wealth effect could be, as they say in economics, asymmetrical. Losses may get us to spend less. But gains in the stock market could be seen as something to be saved, especially after years of financial planners telling us we don’t have nearly enough saved for retirement.

Gross also takes us on a tour of the global economy, in which he says that Venezuela is going bankrupt, Puerto Rico has effectively defaulted, and Japan and China are way over their heads in debt. Here’s what he says about the U.S. and China: (You can read the whole letter here.)

China – Ah, the dragon’s mysteries are slowly surfacing. Total debt/GDP as high as 300%; under the table capital controls; the loss of $1 trillion in reserves to support an overvalued currency; a distorted economic model relying on empty airports, Potemkin village housing, and investment to GDP of 50%, which somehow never seems to transition to a consumer led future. Increasingly, increasingly addled.

U.S. – Well now, the U.S. is impervious to all this, is it not? An 85% internally generated growth model that relies on consumption which in turn, relies on job growth and higher wages, all of which seems to keep on keepin’ on. Somehow, though, even the Fed seems to have doubts, as in last week’s summary statement, where for the first time in 15 years they were unable to assess the “balance of risks”. “We need some time here to understand what is going on”, says Kaplan from the Dallas Fed. Shades of 2007. The household sector has delevered, but the corporate sector never did, and with Investment Grade and High Yield yields 200-1000 basis points higher now, what does that say about future rollover, corporate profits and solvency in many commodity-sensitive areas?

As for Trump, Gross says “now there’s an addled guy … but who knows sometimes they succeed.” The same could be said for the Fed.