Japan is facing a real financial strain as rising interest rates hammer the value of government bonds held across its economy — bad news for insurers, banks, and potentially US markets too.

• Japan's four biggest life insurers are sitting on about $96 billion in paper losses on government bonds.
• The losses come because the Bank of Japan is finally raising rates after decades near zero, and higher rates push down the price of older bonds.
• The BOJ is stuck: raising rates props up the weak yen and fights inflation, but deepens losses across banks, insurers, and pension funds.
• The losses are only on paper for now, but if customers cash out policies early, insurers could be forced to sell bonds and turn those losses real.
• Japan is the largest foreign holder of US government debt, so any shift in how it manages that money could push US borrowing costs up and pressure stocks, gold, and Bitcoin.

Outlook: Watch whether Japan taps dollar-loan tools instead of selling Treasuries, and whether US moves to buy yen start rattling the euro next.