By your reasoning, because cars get faster with time, we should have a Chevy that breaks the speed of light sooner than later. Physics be damned.
You're not a NASCAR fan, are you?
How much faster do you think the cars of today are than the cars of 40 years ago?
The same physics that makes you so all fire certain that no counter-measure will ever be found to the high velocity penetrator will provide that counter-measure. Just because you lack the imagination to envision it does not make it impossible.