Today the reaction to this doctrine is ambivalent; some say that it was a necessary measure in the founding years, while others claim that it amounted to cultural oppression. Others argue that the melting pot policy did not achieve its declared target: for example, the persons born in Israel are more similar from an economic point of view to their parents than to the rest of the population. The policy is generally not practised today though as there is less need for that—the mass immigration waves at Israel's founding have declined. Nevertheless, one fifth of current Israel's Jewish population have immigrated from former Soviet Union in the last two decades. The Jewish population includes other minorities such as Haredi Jews; Furthermore, 20% of Israel's population is Arab. These factors as well as others contribute to the rise of pluralism as a common principle in the last years.