(Seeing as there's a few "What if" topics in the history section, I decided to start one myself, hopefully one that's actually worth discussing.)
I'm sure we all know by now about the sinking of the Titanic in 1912. Well, what do you think would have been different if the Titanic had not struck that iceberg and instead made it to New York as expected?
Obviously, there were about 1500 lives lost with the ship, but I think what really had an impact on history was the changes in safety and regulations in the aftermath of the disaster. I'm not just taking about how there wasn't enough lifeboats for everyone. The closest ship to Titanic at the time of the sinking, the Californian, had shut off their wireless telegraph for the night, meaning they didn't receive any of Titanic's calls for help. Since then, all ships have been required to have their radios on at all times. There was also the formation of the Ice Patrol, which has helped to make sure that, to this day, Titanic remains the latest ship to have been sunk by an iceberg collision.
If the Titanic had not sunk, I think the lack of these updated regulations would have changed history more than the survival of 1500 people. The way I see it, the old outdated regulations wouldn't have stayed the same for much longer, especially once WWI started. If it had not been Titanic, it likely would have been some other disaster to prompt such changes, like the Lusitania. (Not that I think it would specifically be Lusitania, I'm just throwing a name out there.) It's quite possible that many smaller maritime disasters would have happened before such changes are finally made, with a combined loss of life totaling more than the 1500 from Titanic.
Put simply, in my opinion, the changes that were made in the aftermath of the Titanic disaster would have eventually been made, but it would have taken more time to do so, in which time possibly more lives could have been lost than those that went down with Titanic.