While I will agree that aircraft overall do look similar, the Russians have been known to copy Western designs. Here are some examples-
Concorde-TU-144
XB-70-Sukhoi T-4
Space Shuttle-Buran
B-1-TU-160
All these are copies of general concept and not a design.
For example, Buran, while externaly looking similar to SS, dont even have some CONCEPT, let alone same design. SS posses own powerfull engines what helps accelerate during intitial phase - Buran dont. SS should be manually controlled during landing - Buran do it automatically. There are many other important differences.
Tu-160 - again, while looking quite similar externally, is much better performer being almost twice faster than B-1B. They similiraties represent rather similar technological level than anything else. Same with Mig-25 -> F-15-> Mig-29/Su-27 line.
Another importand difference between Tu-160 and B-1B is they armament. B-1B being "almost" conventinal bomber in Tu-22M3 class while Tu-160 is a carrier for ultra-long range nuclear missiles.
Concord vs Tu-144 - no wonder the arey looking similar, after all french and russian design teams had quite close links in initial stage. And again, same technological and airodinamical understanding level...