There is a difference between telling a lie and being A Liar.
Telling a lie means being untruthful - there may be various reasons for it; but being A Liar means that a person does not even try to be truthful. It means that they are habitually dishonest. It means that the truth of their statements and behaviours is subordinated to other strategic priorities - greed, lust, power-craving...
Modern public life is full of Liars and essentially nothing but Liars. It is not that the people sometimes lie it is that truthfulness is simply not a factor in what they say or do - their orientation does not include truth. It is not that they are aiming to be truthful but are weak and set this aside too readily - it is that they are indifferent to truth as a value.
When a wise child knows that somebody is A Liar, they realise that there is no way of sifting truth from them; what A Liar says must be ignored and decisions made on what they have done, not what they say.
Politicians are Liars. It is not that they tell lies - they Are Liars - that is their identity. There is no point in listening to what they say, no point in discussing it - a statement may be true, completely false, or any combination of the two. A statement may be technically accurate, yet creating the opposite impression - everything they say is misleading.
Public Officials are Liars: the mass media are Liars. The leadership of Education, Science, Law, the Military and Police, and major religions are Liars.
Institutions are Liars - all modern institutions that have power, wealth and official authority are now Liars - whether in government, NGOs, charities, colleges, corporations.
The whole modern Establishment are Liars: solidly, systematically, habitually - lying is enforced and rewarded and institutionalised - it is deep, it is solid, it is a positive value.
We should not listen to what Liars say - especially not to what they say they Will Do. We cannot make any sense out of it - it may mean anything or nothing but we have no way of knowing.
We need to make up our own minds about things on the basis of our own criteria - but for Heaven's sake we should not pay attention to debating or analysing their statements.
Liars have no right to expect to be believed about anything. It is outrageous that they do! When (as often) A Liar asks 'Are you calling me A Liar' there can be only two acceptable responses: Say Yes or Say Nothing.
But we should never reassure A Liar that he is believed about anything.
The fact is, if we are wise we will not believe Liars, and nothing they can do or say will make us believe them. The harder they try to make us believe them, the more we should resist believing them - or indeed disbelieving them. What they say means nothing.
Only experience can change our views - if A Liar repents and change his behaviours over a long time despite inexpedient outcomes - then and only then will they cease to be A Liar and earn the right to be believed.