Question

But the Spread of these ships has not been plain sailing. Why is this so?

Answer 1

Answer:

Plain sailing', along with the variants 'smooth sailing' and 'clear sailing', which are more common in the USA than elsewhere, is a nautical phrase that has the literal meaning of 'sailing that is easy and uncomplicated'. All of these variants of the expression are now used figuratively to describe any straightforward and trouble-free activity. There might seem to be be little more to say about 'plain sailing', if it weren't for the existence of the phrase 'plane sailing

Explanation:

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