Optimism is not foolishness for the believer, because hope has invaded history. The future has apocalyptically erupted in the present in the death and resurrection of the Messiah. The new creation has been propelled forward, as a man has been raised from the dead. Furthermore, a community of people have been incorporated into this risen man, and share in his future-present life. The church is thus the signpost of new creation; the gathering of people whose existence points to the way things will be.Quoted from Christians in Context: from orthodoxy to orthopraxy.: Viewing the Present in Light of the Future
And this city, corrupt and broken, is not as it one day will be. God will make all things new, including the created order. Justice will prevail, Jesus will be king, and all will kneel to him as Lord. Reconciliation will be universal and eternal.
The future will not be an endless repetition of the present. The future has already arrived in the death and resurrection of Jesus Christ, and in the constitution of his church. And these events remind us that all will be well, and all manner of things will be well.
I want to view the present through the grid of God's future. If I know that God's righteousness will ultimately and inevitably be demonstrated, then despair is needless and foolish.