Arguing about how many angels can dance on the tip of a needle IMO. If I
remember correctly, the question was: what's the difference between marine
vhf and ssb radio. The plain answer is, you will reach much further with an
ssb and if you don't wander more than 25 miles offshore (where personally, I
wouldn't rely solely on VHF, better be safe than sorry) , you don't need it!
End of line.

Jean

And for the sake of the angels' comfort, here's how ICOM explains the line of
sight issue:

from http://www.ybw.com/ybw/vhf/range.html

How far will your VHF work?

Many customers ask us about the range (distance) over which a radio can
communicate
and it is the most popular question, with the hardest answer.

Radio travels as waves, similar to light. Like light it can be reflected,
reduced or even
stopped by other objects. A popular response to the range question is ‘if you
can see it
you can talk to it’ (known as line-of-sight) and this is generally a good
guide.

Remember however that the radio signal comes from the radio aerial (not the
radio
itself) and therefore using a higher antenna allows the radio to ‘see’
further. The same
rules apply for receiving a signal, although of course base station aerials
are mounted on
very high masts and have much higher power, which is another influencing
factor.

A stronger, more powerful light can be seen further and more clearly and the
same
applies to radio. Power is measured in Watts (abbreviated ‘W’)and the higher
the power
the further the range, but it’s not quite that simple. Even a very low power
can give some
range. Power can be used to improve the quality of signal and to overcome
some
obstacles.

(snip)

Because VHF travels in straight lines, like light, as you travel away from
land the
curvature of the Earth prevents the signal from reaching you. This happens
between
35-50 miles offshore. If you still need to communicate beyond those distances
you need
to look for some other way of doing it.