As we are taught by the מדרש משלי in פרשה ט, in the Messianic Age all the festivals will disappear, except for Purim (and Yom Kippur). The Talner Rebbe, Rabbi Isadore Twersky, זי''ע, taught at his Purim Se'udah in 1996, after a series of bus bombings in Israel, that as Purim will remain with the Jewish people forever, and I quote,
"So Purim is linked to the eternity of the Jewish People - which defies rational explanation, but belief in which is bolstered by empirical evidence. We are now in an עת צרה ; we have to use the energy of שמחת פורים to overcome the threat and to demonstrate once again:
שכל קוויך לא יבושו ולא יכלמו לנצח כל החוסים בך
"--ע''כ דברי אדמו''ר זי''ע
May the זכות of אדמו''ר, the Talner Rebbe, help us reach the final redemption and aid us in achieving the destruction of Amalek.