Because the underlying problem cannot be solved, until all the programs and systems currently in use can be completely rewritten and reimplemented with a widely

Because the underlying problem cannot be solved, until all the programs and systems currently in use can be completely rewritten and reimplemented with a widely-accepted programming language and methodology to ensure correctness and security. If the current approach from the C+Unix era to programming and OS is still in use, there are only three solutions available... 1. Fix-and-miss all the bugs, safe programming practice. 2. Isolation 3. Mitigation Isolation is useful to limit the scope of a security breach but cannot stop attackers from exploiting the bugs. The only solution which is able to stop attackers from exploiting existing programs is mitigation - you don't fix and miss individual bugs, bugs are always there, what we need stop attackers from exploiting them. Some exploits are easy to stop, hence NX. Others can only be stopped in a probabilistic way, hence ASLR.