I remember in the early days of our being in Afghanistan, there were a few media pieces reporting that they remembered the last time the British were there, 100 or 150 years ago. The tone was very much that it was somehow surprising the Afghans brought this up again.
Yet Britain and the US are built on national history, myths and memories. The US has a huge national story around independence and the push west into the frontier. The UK has our tales and myths of 1940 and 1066. Scots still remember "the 45" (that's 1745). Why wouldn't Afghanistan or Iraq?
That said, since Irish independence there has been a good degree of desired closeness between the two countries, not least the passport free freedom of movement and voting, which survived the worst of the NI violence. Looking back that can seem surprising. Record numbers of Brits have been applying for Irish passports (a remarkably high number are eligible) since the Brexit vote.