scramjet

So a scramjet needs needs supersonic air running through it o be able to operate properly.  The problem is, it seems, is that it needs to be something on the order of mach 5 to work.  So the question is, would not it be possible to use forced induction to achieve thrust faster?  One thing that comes immediately to mind is using using the exhaust from a turbojet to help things along, the problem being excessive heat (though in all reality, when flying at hypersonic speeds the heat generated is probably worse than what a normal jet could do).  In action the idea would simply be to duct the turbojet exhaust into the scramjet unit.  Another option that came to mind when thinking of SSTO craft and the possibility of scram-assisted take off, would be to take advantage of the expansive properties of a gas when it heats up, in this case, oxygen.  Regulate the pressure release and use it to achieve scram combustion early.

The last question that comes to mind is that, it seems at some level once ignited, a scramject will keep itself ignited.  is this the case?  Is there any any change that advances in aerospike nozzles could potentially ease the barrier to entry or is a rigid de Laval nozzle essential for this particular type of jet?

Thoughts anyone?

>>7
But RedCream, why is there a glowing hammer and sickle floating in the sky?