Imagine: You’re out at sea, sailing through treacherous and uncharted waters. The tips of sharp rocks jutting from the waves give some forewarning of danger, but beneath the surface, twisting reefs and shallow sandbanks threaten to run you aground.

Imagine: You’re out at sea, sailing through treacherous and uncharted waters. The tips of sharp rocks jutting from the waves give some forewarning of danger, but beneath the surface, twisting reefs and shallow sandbanks threaten to run you aground.