Protestant Reformed covenant theology is not replacement theology. God hasn't broken a single promise to Israel, because they are all fulfilled in Jesus (2 Cor. 1:20). Ethnic Jews who believe in Christ are no longer Jewish in any meaningful sense (Gal. 6:15), because in the body of Christ—the church—there is no such distinction as Jew vs. Gentile (Eph. 2; Gal. 3:23-29). On the other hand, Jews who reject Jesus have abandoned the covenant promises of God and have no claim to any blessings of God (John 5:39-47). What blessings of God can there be for those--Jew or not--who reject Jesus? Of course, the message of the gospel is for ethnic Jews as much as for non-ethnic Jews: "All who call upon the name of the Lord [Jesus] shall be saved."
I do not support Palestinian terrorists or terrorists of any type, regardless of who they are attacking. I believe that Israel has every right to defend their borders and their people, just like any other nation. At the same time, we should not expect God to bless Israel as long as they reject Jesus and persecute his church (which they do). I pray that many within Israel would repent and trust in Christ as well so that they might know the blessings and salvation of Christ.
See the excellent article by Pastor Jeff Meyers "Forever Means Forever"