March Charts, page-91

I wouldn't agree with fully fledged world wide collapse, but the catalyst for a decent pull back in markets is higher inflation, due to the strong global growth as you say. It is the good news around global growth that is the bad news, particularly if inflation rises quickly, which would mean central banks (governments) need to raise interest rates quickly to avoid an overheated economy.

Higher interest rates are a problem, because at some point rising rates could stall said economic growth. The other issue with higher interest rates, is that there are mountains of debt out there (i.e. 3 x global GDP). Higher interest rates are not conducive to higher asset prices, in that your real return on investment is reduced after allowing for higher inflation. If inflation and rates rise quickly, hang onto your hat, if they continue to grind up slowly, maybe markets can remain reasonably steady as she goes.