Romans 11 addresses this. They were allowed to become disobedient so that they may fall and provide opportunity for the Gentiles to be grafted in with faith. This also provides opportunity for them to recieve mercy and be grafted back in once they stop persisting in their disbelief and being from the original plant, those who have faith and become grafted back in will take more greatly than the branches of the Gentiles for whom room was made.
They are made enemies for our sake but loved by God. This clinging to salvation via works they hold to with the yoke of the law is the stumbling block by which they fall and that same block is the chief cornerstone that has allowed us who are not Jews to have opportunity to come to God as adopted children in Christ. Just as God enjoys giving mercy, so should we rejoice for the few of them who will be brought back in when the time comes.
Those who remain fallen in disbelief seek to burden us with the yoke of their law so that we might be accredited to them under it, not understanding that it is the law that condemns them so that they might know sin and be made able to recieve the mercy that magnifies God's glory and gives purpose to their existence.