HaKatan,
Mashiach ben Yosef did come in 5708. The Zohar says that easch 1,000 years of creation is lagainst one of the first six. That means that 5708 is the sof zeman bittul chametz. There is no greater chametz than the galut.
BTW, Rav Soloveichik said that if not for the creation of the State of Israel Jews would have assimilated completely. Missionaries were using the Holocaust as proof that they were right. RS himself was accosted a number of times during his trips between Boston and New York. The creation of the State destroyed their whole sheeta. This is besides the great mitzvot of establishing a sovereign state in Eretz Yisrael (which was heralded by almost all of the gedolim in Eretz Yisrael, including the Agudaistim), building the Land and being mosser nefesh to save Jews.