Was Haman the last Amalekite? If so, is there any way to fulfill the physical mitzvah of obliterating Amalek today?

Haman is called "Agagi", apparently meaning he is a descendent of Agag, the last king of Amalek. Since the Purim story takes place aproximately 600 years after Shaul destroyed Amalek, it stands to reason that some of Agag's descendants survived, so in the physical sense, Haman may not be the "last" of Amalek. Even if it would be impossible to recognize an Amalekite today, the Mitzvah to eradicate the memory of Amaleke demands that we attemt to eradicate the type of evil that Amalek represents. Since the Amalekites were a tribe of nomadic slave tarders, protesting human traffiking (the modern slave trade) and upholding standards of human dignity is a way of destroying Amalek. It may be that any regime of group (Stalinism, Nazis) that seeks to destroy the Jewish people is a form of Amalek.