Adam Smith is misunderstood
Adam Smith was first and foremost a moralist, and his primary concern was the perverse incentives of business owners and property owners, given power, to subvert the national wealth for their own ends. Hence he first had to show how the wealth of the nation came about - through pursuit of self interest. So Smith's writings were about the morality of the politico-economic system, not just economics.
We now know that the basis of economics is trust, of which money is just a convenient form. Trust in institutions accounts for all of the difference in average income between a state like Somalia and the UK, or 99.5% of the average British income. Loss of trust destroys wealth, as happened in 2008 when the banking system lost trust in the CDO, sending the world into recession. Crashes are due to sudden and contagious loss of trust. Trust is hard to gain, easy to lose.
Laissez-faire liberalism is a cargo-cult version of free markets, ignoring the many assumptions which are necessary for perfectly competitive free markets to work without regulation - including the fact that we are far from "Homo Economicus". It will fail, and it is failing in the USA and UK, as the gap between rich and average continues to widen.