There are two Jerusalems, the city in Israel and a heavenly Jerusalem which will come down from heaven. Both Jerusalem’s are joined in the mystery of Jesus and Mary.
When Jesus returns in glory, the heavenly Jerusalem will descend. However, the Father cannot wait. He placed the gifts of the heavenly Jerusalem in the Immaculate Heart, and He wants Our Lady to distribute them as a foretaste of Jesus’ second coming.
The earthly Jerusalem will be the sign. This city will come under siege, a trophy that Satan wants to carry away. However, Jerusalem will remain in God’s hands, besieged but not conquered, (as in the time of Isaiah). This will be a modern sign that Jerusalem belongs to the Father.