Using lasers to communicate

[SINCLAIR DOUGLAS N]

> If you have a secure link you don't need encryption.  Arguably, the
> converse is true; if you have secure encryption you don't need
> a secure link.  Isn't the ability to transmit secure data over
> insecure channels one of the primary justifications for encryption?
> 

Of course.  My point, though I seem to have failed to state it,
is that encryption is a cheap software thing while laser beams
are expensive, complicated, and still not secure.