JGB Yields Approach 30-Year Highs as SocGen Warns of Global Valuation Shock
Taylor Wilson
Japan's 10-year government bond yield hit 2.88%, the highest since 1996. SocGen strategist Albert Edwards warns that if cheap Japanese capital retreats, US equities trading above 20× forward P/E may not hold.
How far have Japanese bond yields risen?
The 10-year JGB yield climbed to 2.88% on Thursday — its highest since September 1996 — marking nine straight days of gains, the longest streak in nearly two decades.
The 20-year yield surged to multi-decade highs in tandem. Ultra-long JGB yields now exceed Germany's and approach Spain's.
This means → the world's last "ultra-low-rate fortress" is being forcibly repriced by the market.
Why is the yield curve flashing an abnormal signal?
The spread between 10-year and 2-year JGBs widened to 143 basis points, the widest since 2004. In plain terms = long-dated bonds are selling off hard while short-dated bonds barely move — the two ends are diverging sharply.
Daiwa Securities senior economist Kento Minami called the steepening "an alarm bell from investors," pointing to a clear disconnect between risk as the market prices it and the government's fiscal and monetary stance.
Mitsubishi UFJ Asset Management's Masayuki Koguchi noted that relative to current inflation, the 10-year yield is still too low — and must rise further as prices climb.
Demand at last week's 10-year JGB auction fell to the lowest since April. Even at multi-decade highs, buyers have not returned.
How did fiscal expansion plans light the fuse?
PM Shigeru Takaichi's government disclosed plans for over ¥370 trillion in combined public-private investment through FY2040, while floating a cut in the food consumption tax to 1% — with no clear funding source.
Mizuho Securities analysts noted that markets now see the Takaichi administration as treating easy monetary policy as a prerequisite for growth — and therefore "unlikely to welcome" rate hikes. This means → political pressure has sharply narrowed the BOJ's room to tighten.
The yen is already casting a vote of no confidence: JGB yields are surging, yet the yen keeps weakening — defying textbook economics. Sources say the government is already considering revising the wording of its economic blueprint to calm the bond selloff.
Why does Edwards call this a global risk?
He compared the current Japanese market disruption to the 2022 UK "mini-budget" crisis under Liz Truss, arguing a financial storm capable of hitting global asset valuations may be brewing.
The core logic: for decades, Japan's suppressed bond yields and excess QE liquidity provided a massive tailwind for global equity and bond valuations. In plain terms = Japan has been the world's biggest cheap-capital tap, and that tap is now closing.
He posed a direct question: if the 10-year JGB yield keeps climbing toward 4%, can US equities sustain a forward P/E above 20×? His answer: "I don't think they can."
What links the AI investment boom to the retreat of cheap capital?
Edwards cited a recent Bank for International Settlements (BIS) warning: if the current AI investment boom under-delivers economically, it could become a "prolonged investment bust."
He drew parallels to the 1830s canal mania, 1840s railway expansion, and late-1990s internet bubble. This reflects his core fear — competitive capacity buildouts fed by cheap money have ended in collapse every single time in history.
This means → if Japan's cheap-capital retreat and a peaking AI investment cycle coincide, the combined shock would far exceed either event alone.
What is the market watching next?
The BOJ raised its short-term policy rate to 1% in mid-June. Swap markets imply an 87% probability of another 25-basis-point hike by December.
The market's verdict, however, is that this pace is far too slow given returning inflation and fiscal expansion impulses.
In plain terms = whether JGB yields can stabilize at current levels is the key test of global investor confidence in Japan. If they cannot, Edwards's warning moves from commentary to reality.
Content is for reference only, not financial advice.