Drive safe, especially when others don't

Earlier today I was merging onto a dual carriageway and when I came down the slip road I came alongside a lorry doing approximately 50mph. Rather than try to floor it uphill to get in front, I eased off a little to slip in behind. The tanker lorry behind the lorry did not see or did not care, and significantly closed the gap such that I had to brake to slip in behind them. I was fortunate there was no one behind me. If you drive a large piece of metal, please try not to hit the ones with smaller pieces of metal.