This is the latest in a series of occasional articles on the shared histories of Bermuda and the United States, which celebrates the 250th anniversary of its independence this year. The articles, by Heritage Matters author Edward Cecil Harris, will run throughout the year.

For this small place, the phrase “unintended consequences” took on considerable meaning in the 1800s and indeed into the 1950s. We speak not of the sometimes-contrary consequences, like importing birds to eat lizards or crabs, but of “unexpected benefits”, perhaps serendipitous events, that increased the wealth of Bermuda without measure.

Those here who like to “trash” the United States, commonly known as “America”, know not of which side your bread is buttered or indeed if you are eating leftover pork rind or non-gluten sponge cake. The fact is that the Independence of America had the unintended consequence of making Bermuda one of the wealthiest places on Earth in the last 250 years.

In this instance, I speak not of all the US dollars in our banks, the currency of wealth, but of the extraordinary gifts embedded in the land by way of military monuments, now paying us hand over fist in heritage and tourism dollars.

The Bermuda Dockyard is the shining example of that unintended gift of the Americans, although glimmering is perhaps not applicable to all heritage “handled” by central authorities, starting in 1953.

You must go back to the beginning to appreciate the scale of the benefits that arose after 1783, before which Bermuda was first a sleepy company town (1609 to 1684) and then a backwater islet of a burgeoning British Empire.

Yes, yes, after 1684, with our Bermuda rig and classic, fastest-afloat Bermuda sloops, and a bit of privateering thievery, we were starting to accumulate wealth, but that was an income source doomed by the new technology of iron boats and steam engines.

Before 1783, public expenditure on fortifications was minuscule and while dozens of fortlets were constructed, most would have been demolished with one hit from a small Ukrainian drone, no worries.

Then came independence and the British military awoke to the realisation that Bermuda could be the bit in the mouth of the American horse, by which its “propensity for violence” (to paraphrase one English officer) could be controlled. To that end, the “bit” involved serious mouthfuls of British sterling expended in Bermuda over two centuries (1783 to 1995) on fortifying and garrisoning the island to keep the American stallion in check.

As an unintended consequence of independence, military cash poured into Bermuda, created jobs across the employment spectrum, which may have caused some of the migration from the British West Indies to the island over many decades. We had the jobs and the funding and if you had a British passport, you could come freely to Bermuda, no “work permit”, blah, blah, until around 1957 when laws changed apparently.

The boom started with Major Andrew Durnford and the Royal Engineers who came to the island right after 1783 to assess the fortifications for “military preparedness”.

The existing monuments were found lacking, so naturally “jobs for the boys” began with the building of new forts and upgrading of the old. My many-times-great-grandfather, James Whitecross, was found in documents to be working with Durnford at Castle Island, and perhaps also on the very nice, yet-existing, Durnford House at the gateway to St George’s (where Andy also became its first mayor, ha).

The real corker came in 1809 when the Royal Naval Dockyard began to be constructed on westerly “Ireland Island” (Mr Ireland’s land and that of other Bermuda families thereabouts were compulsorily purchased for the base).

Billions were expended into the local economy on its construction and maintenance right up until 1995, when sadly, no thanks to the Russians, the Cold War melted and the London Ministry of Defence turned off the Bermuda cash siphon.

In the lowest of the lower parishes, St George’s, the economy boiled over as expenditures blossomed, like oleanders in spring, with the construction of five major forts, including the now well-maintained Fort St Catherine.

Across the spectrum, Bermudians were employed on the construction, in the supply of materials, like stone and lime, and in the many other necessities, such as housing and feeding the British military.

It may thus be contended that the foundational wealth of modern Bermuda is to be found in the cornerstones of every British military work on the island from the 1800s, many now part of our Unesco World Heritage Site.

Today, anyone visiting Fort St Catherine, Fort Hamilton, Scaur Hill Fort and the Dockyard knows the value of those monuments to the economy of the island. They are all the unintended gifts of our American cousins, whose Independence paved the way for our modern wellbeing.

And this is to say nothing for the moment of the benefits that came to Bermuda with the American bases in the heat of the Second World War.

• Dr Edward Harris is the founding executive director emeritus of the National Museum of Bermuda