I've tried figuring out if there's a particular episode that this might refer to, but I can't come up with one. Despite inevitably differing strategic priorities, financial strains and a degree of parting of the ways through US non-ratification of the Paris treaties, relations were generally good throughout the period.

I thought perhaps there was a surge in US agitation over Ireland, but recognition of the Dáil government was defeated at both 1920 party conventions, despite widespread support among Democrats who in any case spent the following decade out of power.

There was a moment of disagreement at the start of the period over US naval construction, but the matter was resolved fairly painlessly at the Washington Conference in 1922 with agreement for British-US parity in capital ships. The two sides failed to agree on cruisers at Geneva in 1927 but a compromise was found at London in 1930.

A chronic issue in the early years (and again a decade later) was that of inter-Allied war debt, of which Britain owed $4½ billion to the US: British requests for a general easing of terms until it could recover part of the still greater amount owed to it by other former allies (much of the latter in turn reliant on reparations from Germany) met with a blunt rebuff, and London settled in 1923 despite still being in the depths of the post-war slump from which the US had recovered.

Despite US absence from the League of Nations and avoidance of strategic entanglements, Washington took part in many of the international conferences and initiatives of the period, the two countries again tending to co-operate as on restructuring German reparations through the Dawes and Young plans.

So the two powers got along remarkably well despite occasional differences, and there's no sign of anything approaching a war scare or even threatening hostile agitation between the two countries in the period.