The most effective way to protect earth from killer asteroids is to mine them out. This will be done by private industry as soon as the Treaty becomes a non-issue. Those who propose to go around the Treaty like the idea of scoundrels flaunting the law but ignore the fact that the scoundrels are all talk and no funding while the Treaty in in force.
The most effective way to protect earth from killer asteroids is to mine them out.The most economically effective way, yes, and it is going to get done. Of course, it would happen faster if an upcoming threat were found (not that one which will hit in 800 years).