Meanwhile, despite starting the year strongly, European stocks have faded away when compared with those in the US. Why?
Long-term fixed-rate mortgages and being energy independent have reduced the impact of higher bond yields and commodity prices.
And, so far in 2023, the technology sector has soared, which has helped the US market.
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For overseas investors, it is also to do with the currency; in times of market stress, when equities are most at risk, the US dollar tends to perform well as a safe-haven asset.
But there is another factor to consider - the impact of productivity and innovation, which are higher in the US than most other developed Western economies.
The recent launch of generative artificial intelligence software tools is a great example of this.
There are few pure plays for investors on this theme; Nvidia, the obvious one, is US-based. The others with exposure, and significant balance sheets to pursue generative AI projects - Microsoft, Meta, Alphabet - are again all US-based.
And even where there is little appetite to spend on internal innovation, the US is far more willing to acquire interesting innovation quickly.
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As an example of this, Thompson Reuters, which has a legal research business, Westlaw, decided to spend $650m to acquire CaseText, a legal startup whose main product CoCounsel is a GPT-4 AI legal assistant.
CaseText was an early adopter of OpenAI's services, and it has been rewarded for its foresight.
Despite academic evidence suggesting M&A is generally not worth the time or capital, there are various examples of acquisitions which have created enormous shareholder value for American companies.
The global regulatory environment around acquisitions is evolving, but so far it has seemed that American companies are better at finding hidden gems to acquire, something which is expected to continue.
Aided by the undisputed political might of the US, American companies are more likely to find paths forward when others cannot.
Just look at the UK CMA's response to Microsoft's proposed acquisition of Activision, initially rejecting it after a review only to realise later that it was the only roadblocks to the deal among global regulators. The UK CMA has now found another route to approve the deal without damaging its credibility too much.
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More broadly, you could argue US innovation has disproportionately helped the technology sector, but we think it also impacts the entire economy.
This year the huge outperformance of the 'Magnificent 7' (Microsoft, Apple, Alphabet, Tesla, Nvidia, Meta and Amazon) corroborates this notion, but innovation also lies in other parts of the market as well, be it in Edwards Lifesciences, NuScale Power or Kornit Digital.
With leading innovation and a deep pool of capital, US companies have attracted higher valuations than those listed elsewhere, and as a result, its stock markets have been able to attract IPOs from around the world.
These factors put US equities in prime position when allocating capital on a global basis, while all other Western economies struggle to keep up.
For us, this is an important consideration in our portfolios and, despite generally higher valuations than elsewhere, the US continues to provide compelling opportunities for investment.
In our view, it is appropriate to maintain significant exposure to this geography.
Mike Willans is head of equities at Canada Life Asset Management and Bimal Patel is a senior fund manager on the global equities team