...and in the forties and fifties, Britain was still recovering from the ravages of war. The Labour Government of the late forties nationalised (= destroyed) everything in sight, smashing any hopes we had of capitalising on our innovations.
Of course, our small home market (and the domination of Government-owned BEA & BOAC in that market) was also critical.
In comparison with the US, Britain was poor, with far fewer people flying or having the means to. So our airline industry remained feeble until the advent of the inclusive holiday in the late sixties. By then, most of the airframe manufacturing industry had gone.
Also, in comparison with the US, we were poor salesmen, only managing to sell a few export orders. I remember that MEA purchased 707s in preference to VC10s because the Boeing salesmen did a deal involving Lebanese oranges!