A lying politician surprises you? They ALL lie.
What's important is not THAT they lie, but WHY they lie. WE force them to lie in order to get elected. It's that simple. If someone came out and announced themselves as a candidate, and did nothing but tell the unvarnished truth to the American people, they would not receive a single vote.
We live in a society that never wants to hear the words 'sacrifice' or 'responsibility'. They want to hear that their taxes will be lowered and they will receive more 'free' stuff from the government, but it never occurs to them that those 2 things are mutually exclusive.
They always want everyone else's taxes raised, while they themselves receive all the 'free' stuff paid for with those taxes. That is, of course, impossible, so the politicians do the only thing they can. Borrow the money. That way they can buy votes by lowering taxes, AND buy votes with 'free' stuff.
If a politician tried to run for office by telling America, "Well, here's the truth. In order to avoid the eventual complete collapse of the country, we are going to have to raise taxes on everyone, AND cut government hand-outs to both corporations and individuals to near zero for the next decade." That would be the end of that person's political career.
In short, elected politicians are a reflection of the electorate. That's why we don't get the politicians we want, but instead get the politicians we deserve.
America IS Donald Trump. Loud, crass, amoral, disrespectful, self-indulgent, self-centered, egotistical, and on and on. Expecting the politicians to change without the people doing so first, is illogical.