They buried the hatchet, but in a shallow grave.

A humorous twist on the idiom “bury the hatchet” appears in early-1900s newspaper writing about political or personal truces that are expected to fail. The earliest located evidence is from 1901, first in a letter by Thomas Kirby in an English paper using the “shallow grave” idea, and shortly after in an Indiana newspaper item using nearly the modern phrasing. Decades later, Reader’s Digest credited a version to Dorothy Walworth, which likely helped spread that attribution.

The line implies that a supposed reconciliation is superficial and temporary: the conflict is only barely put away and can be quickly revived.

It is said that Croker and Hill have buried the hatchet. It is in a shallow grave, however, and will be resurrected at the least provocation.

They buried the hatchet, but in a shallow, well-marked grave.

How shallow the grave of the buried hatchet!