The semiconductor industry generates greater $300 Billion annualy in gross sales. The majority of sales are associated with silicon. A hiccup in this industry, say if Moore's Law is finally reached then a collapse in the global economy could happen and quickly!
Would you upgrade your current computer if it provided no increase in performance? Would companies update server farms if yesterday's technology is just as good? Would you pay ten times the amount for a computer or mobile device with new composite chips that may replace silicon chips? Probably not. This could rapidly slow computer upgrades and replacements and could conceivabally throw the world into a recession or worse. This potential tech correction would be larger than the dot.com bust of the early 2000s.
So what uses are so important that the world cannot live without it?
For starters your phone's microchips.
Your current vehicle's sensors.
The future Driverless vehicle sensors.