The bond market has a sleepy reputation, but it can pack a punch when alarmed. And worries are now growing about tax cuts pushed by Washington and how they'll inflate the U.S. government's debt.

"Major financial events often happen first in Japan, for example the late-1990s tech bubble bursting first in Japan," Albert Edwards wrote Thursday.

In the past, when bonds sold off, it typically was seen as a promising sign for stocks. It meant that traders were betting on a stronger economy — but not this time.

From ho-hum debt auctions to plunging long-term bond prices, investors are sending a clear message to governments that in the current climate of uncertainty they need to pay more to borrow for decades ahead.

Bond yields have spiked this week on investor concern over the tax bill swelling the US deficit. Here's why markets are worried.

The Japanese government bond market was already having a bit of a springtime nightmare, but a poor auction of 20-year debt earlier this week has sent long-end yields soaring to their highest levels ever.

The trade war has calmed down, but rising government borrowing costs pose a new worry.

Japan's super-long government bond yields have spiked to record highs, as mounting political calls for tax cuts and big spending draw investors' attention to the country's fiscal woes.

Bank of Japan Governor Kazuo Ueda refrained from indicating he’s prepared to take action in the bond market after yields on super-long dated securities hit a record high, amid a continuing effort to improve trading conditions.