I see what you mean. I think it's probably a case of 'convergent evolution', where two planes designed for the same sort of thing (size and speed in this case)

I see what you mean. I think it's probably a case of 'convergent evolution', where two planes designed for the same sort of thing (size and speed in this case) come out looking sort of similar to each other. The American B-1 Lancer and the Russian Tu-160 look quite similar to each other for instance, but to my knowledge neither is a ripoff of the other.