IF we follow (of which we do not) Soviet

doctrine, that would be fine. And might as well procure S-400 instead of any western made system. Furthermore, long range interception is the domain of interceptor & fighter plane, NOT missile. Again, there is little tactical sense in using long range SAM other than for BMD role.
That being said, It's bring us to the choice of BMD system. Which BMD system we intend to procure

The

doesn't allow foreign operator of their system. If we procure it, then it will be all

crew whose manning it. While

made system (Aster 30 BMD) still in development. That still doesn't take into account the other supplementary system that one need to effectively operate BMD system or any modern air defence system, such as integrated datalink, EW (counter jamming, etc) of which we severely lack of. I can go further to tactical deployment aspect, but that would make this a rather long post.