Okay what the hell is going on with Japan ??? 
And how might this affect us over here in the USA ???
"Japan is considering a $110 billion stimulus package and that's the reason bond yields are spiking right now. Japan already has insane debt at over 230% of GDP. When you're already drowning in that much debt announcing more spending without raising taxes or cutting anything else sends a clear message to the market that this government doesn't care about fiscal sustainability. Bond investors immediately lose confidence because they're thinking, how are they going to pay this back? So they demand higher yields to compensate for that risk. "
"The stimulus itself is focused on tax cuts, energy subsidies, and cost of living relief. This all sounds great but here's the problemyou're cutting taxes and spending more money while your central bank (the BoJ) is trying to normalize policy by raising rates. That's a contradiction. The BoJ wants to tighten monetary policy but the government is loosening fiscal policy. That forces the BoJ to keep rates low to avoid crushing the economy. "
"Here's where the real rates problem comes in. The BoJ's policy rate is 0.5% and that sounds positive. But inflation in Japan is running around 3%. So the real interest rate (nominal minus inflation) is actually negative 2.5%. That's the problem. When real rates are that negative, you're losing money by holding yen. If you deposit money in a Japanese bank earning 0.5% while prices rise 3%, you're down 2.5% in purchasing power. Nobody wants that. So investors pull money out of yen assets and buy other assets instead, where they actually earn real returns. The yen gets destroyed"
"So the stimulus package is actually guaranteeing that the yen gets weaker. A weaker yen means import costs go up food, energy, materials everything gets more expensive. The whole point of the stimulus was to help households with cost of living but the fiscal expansion is simultaneously destroying the purchasing power of the yen. It's counterproductive. You're giving people tax cuts with one hand and taking away their purchasing power with the other through currency depreciation and import inflation. That's why bond yields are rising, the market sees this and knows it's unsustainable."