The passuk says – atem eydai – you are My witnesses.
This means that as the chosen people, we very often do not do what we are meant to do, but still kol yisroel yesh lahem chelek leolam haba becuase the purpose of our existence transcends the limits of olam hazeh.
If someone dies becuase they are Jewish, that means they have left an indelible marker in history that there was such a thing as a Jew.