To The Moon

On Monday, U.K. Treasury chief, Jeremy Hunt, rolled back about £32 billion of the £45 billion in tax cuts promised by his predecessor.

In its game of chicken with the U.K. government, the Bank of England has emerged victorious. Investors are relieved, but in truth nobody has much to celebrate.

On Monday, U.K. Treasury chief Jeremy Huntrolled back £32 billion, equivalent to about $36 billion, out of the £45 billion in tax cuts promised by his predecessorKwasi Kwarteng. British sovereign bonds rallied, particularly those with shorter maturities.

BOE Gov. Andrew Bailey’s gamble paid off. Last week, he reiterated that bond buying wouldn’t be extended, putting the pension-fund industry at risk. Gilts set the price for U.K. government borrowing but also are key for financial stability, so neither the BOE nor the Treasury could afford to let the volatility sparked by Mr. Kwarteng’s plans persist. But the government blinked first, after financial instability sparked a rebellion within the Conservative Party.

The incident highlights why investors shouldre-evaluate bonds. Yields can only go so high relative to interest-rate expectations before officials are forced to intervene one way or another. The message for politicians is also clear: Even if central bankers ultimately step in during a crisis, antagonizing them can easily backfire, because they are harder to remove than elected officials.

Contrary to recent chatter in the City of London and on Wall Street, though, it is doubtful investors ever genuinely feared so-called fiscal domination: U.K. politicians overriding the BOE and creating endless inflation. If that were the case, sterling’s initial drop against the eurowouldn’t have reversed so quickly.

But this also means that Mr. Hunt’s U-turn doesn’t provide the economy, or the pound, with much upside from here.

While it is good that Mr. Kwarteng’sill-conceived tax cutshave been canceled, U.K. policy is now more aimless than ever, trapped between another potential leadership battle and the prospect of a straight-jacketed government until as late as January 2025—the deadline for a parliamentary election. Mr. Hunt seems to be focused on reducing bond yields over the next two weeks so that, when the U.K.’s independent fiscal watchdog publishes its medium-term projections for public debt, they are a bit less scary. At current levels, a flat debt-to-output ratio in three years’ time would demand £40 billion more in annual savings, according toSamuel Tombsat Pantheon Macroeconomics.

“All departments will need to redouble their efforts to find savings and some areas of spending will need to be cut,” Mr. Hunt said Monday.

Such talk echoes the fiscal orthodoxy that sapped U.K. growth in the 2010s. Even the inflation-reducing energy-bill cap is set to be redrawn next year to reduce expenses. Public-sector austerity has become yet another risk for the country’s economy, on top of rising energy and mortgage costs and a shrinking labor force.

After Monday’s gilt-market rally, yields remain elevated. The problem is that they are determined more by the central bank than by the stock of government debt, and the BOE finds it easier to ignore concerns other than high inflation. It has refused to act more decisively to help pension funds unwind their leverage quickly—leverage motivated by accounting standards enforced by regulators—and even remains committed to selling its own bond portfolio. Since Mr. Baileysaid in a speech Saturdaythat these bond sales aren’t part of setting monetary policy, the only rationale for not suspending them can be establishing its own supremacy over the Treasury.

An important learning from the post-2008 period was that some coordination between governments and central banks can lead to better outcomes. As the U.K. has so dramatically shown, this also risks getting eroded by rising interest rates.