Interesting points and perspective.
2 counterpoints:
#1) Don't you think that commercial miners are well aware of the
subsidy schedule and have worked that into their business plans?
Yes, I
believe that they have. I
hope that they have done so correctly and without making business plans involving malign intent.
#2) Even if jarring displacements occur as you speak of, I
don't understand what conditions there could be that would
make attacking more profitable than mining. Can you give
an example?
Sure. Terrorist wants to spread chaos and make a profit to arm and equip his jihadis. He acquires massive hashing infrastructure which miners are getting rid of on a secondary market like ebay for cheap, shorts Bitcoin with sixty-day contracts, and starts doing double spends of large amounts, forcing orphaning of chains hours or even days deep. This will attract media attention and shatter confidence in Bitcoin security, as well as inspiring people to wait longer and longer and let the blockchain get days deep before they consider a payment secure, so he gets profits from his double spends, a huge payback on his short, and as a bonus, strikes a blow against the capitalist swine by destroying the value of their Bitcoin.