The Bible is not just a book of history, but is also a book of prophecy. That is, it speaks about events that, at that moment in time, had not happened, but eventually would.
In some cases, these things have not yet been fulfilled. The Tribulation, the Millennial Kingdom, the White Throne Judgement, and of course the end of the first heaven and earth followed by an eternity in Heaven (for believers) or Hell (for unbelievers). These are all things that have not yet happened, and so for an unbeliever, it's not really worth much to hear about it. But for a Christian, these things should be of paramount importance, and yet Jesus said we must believe Him about earthly things to believe Him about Heavenly things (John 3:12). In other words, if you are not a Creationist, you might as well not believe Him about Heaven.
But in other cases, while the prophecies were not fulfilled to the writer, we have long passed their expiration date. Thus, we can verify whether or not they came to pass. They did. In fact, Christianity is the only religion that can boast of a 100% prophecy success rate. Even Judaism, which follows the Old Testament, cannot boast about this if they reject Jesus as the fulfilment of Messianic prophecy, because if Jesus is not the Messiah, Messianic prophecy failed. And yet, Christianity is based on the fulfilment of the Old Testament. If the Old Testament contained just one failed prophecy, Christianity could not exist.
So, there was a time when God was the only living being to have seen the future, and He was able to describe that future to and through His prophets. History then progressed in exactly the way He predicted, so much so in some cases that sceptics actually try (and fail abysmally) to change the authorship dates of some scriptures, thus allowing them to pretend it's not an accurate prophecy, but an accurate description of history. Ironically, they use circular reasoning in doing so. The only "proof" they have that Daniel, for example, was written later is precisely because it so accurately records history, and in their eyes, prophecy is impossible, so Daniel must have been written later.
Similarly, today, God is the only living being who saw creation (not counting the angels, as we can't exactly ask them). As Christians, we need to ask what logic there is in believing God when it comes to prophecy, but not when it comes to history? As unbelievers, you have to justify believing that God, who is so good at predicting the future, is so inept at telling you the past.
Whether you're a Christian or an unbeliever, opposition to Creationism just makes no sense in light of prophecy. God's reliability has been repeatedly demonstrated in the fulfilment of prophecy. God's promises about the future are pointless if we don't believe Him about the past. In both scenarios, Creationism is the only view of origins that makes sense.