They're not the same. Obama lied and he knew it when he said it. With Bush, he was persuaded to change his views. Like you said, Bush believed what he was saying when he said "no new taxes". When Obama said "if you like your doctor/ins, you can keep it" he KNEW it was a lie. And as far as Trump's lies go, name one that has cost me a dollar.
Let me do it, please. Consider this one lie, "Mexico will pay for the Wall". Surely you are not so naive to think that's not costing any of us more than a dollar!