Yes, some day we will see a better world - and not only a better world, but a perfect world - one that will be free of all the evils and injustices that plague us now. But the Bible says this will only happen when Jesus Christ comes again to set up His kingdom of righteousness and peace.
Why can't we seem to make any progress toward world peace? It isn't for lack of trying; governments and diplomats work for it all the time. And sometimes their efforts meet with a degree of success - at least for a time. This is one reason why the Bible tells us to pray for our leaders, because God's will is for us to live in peace (see 1 Timothy 2:1-2).
But eventually their hopes are dashed, and conflicts and wars once again break out. What's the problem? The problem is within ourselves - within our own hearts and minds. Selfishness, greed, hatred, a yearning for revenge - these destructive yearnings all come from within, and lead eventually to war. The Bible says, "What causes fights and quarrels among you? Don't they come from your desires that battle within you?" (James 4:1).