Why do liberals tell so many lies about supply side economics?

They are free to lie because they are liberal. But how can you know due to your prejudice that they are lying.

Not many economists are Liberal Democrats, but most economists can explain to you why the "build it and they will come" Supply-Side economics approach simply does not work. If you are old enough to be a parent, try this analogy to describe the "sugar effect" of Supply Side fiscal policies: An indulgent parent gives a spoiled-brat toddler a bunch of sugary snacks just before a nutritious meal, with predictable results (as most parents can describe)---the energy level goes sky high almost to the frantic level, then abruptly BURNS OUT and the toddler then crashes to below the energy level that was in place just prior to all that sugar consumption. To make matters worse, once that sugar-high hit, the kid had no appetite for the nutritious stuff that would have helped sustain a more moderate energy level.

Demand-Side economics, on the other hand, is what FDR, Bill Clinton, and President Obama have put into place to help grow the economy from the lower levels on upward and outward in an ever-expanding economic growth spiral. Targeting tax cuts to the lower income workers means more spending money, and consumer spending (demand) helps shop owners move their inventory, thus turning a profit, which can mean hiring more workers to keep up with the demand (more pay to spend, more payroll taxes for revenue generation) and also ordering more supplies, which helps the shipping industry and the manufacturing industry, who then hire more workers to handle the INCREASED DEMAND, and those new hires spend money (even more demand) and so on upward and outward until all levels are prosperous.

Supply-side causes depression after a short-lived energy spurt that burns out fast---no nutritional value.

You gave yourself away when you said "when the people who have almost all of everyone's money..."

The money doesn't belong to everyone, it belongs to those who earn it.

Your whole analysis is nothing more than an ideological rant, and is refuted by history.

Almost all of the Bush tax cuts went to the richest people.

No, they don't get us out of recessions.

When almost everyone has no money, then only a few people can spend money, buying goods and services; therefore, there are no jobs.

When most people have money, it drives up demand, and creates jobs.

It's conservatives who constantly lie. When extremely rich people pay little or no tax, it does NOT enrich everyone; it impoverishes everyone except those rich few. When the financial industry is deregulated, greedy, unscrupulous people take everyone's money, and wreck the economy -- it does NOT lead to prosperity for all or most.

And Bush's tax cuts, especially coupled with his unfunded wars, ballooned the debt. The one Reagan had already tripled when he was in office.

When the people who have almost all of everyone's money don't pay taxes, it does NOT increase revenue.

Everything conservatives say is wrong.

Republicans lie like normal people breathe.

If they get us out of recessions how do you explain the GFC?