An argument does not have to be correct to be cogent. There are a few on the left who do, in fact, have cogent arguments. That is true in economics and other areas, as well as climate change.
Actually the same is true on the right. For example, most arguments on immigration, trade policy, gay marriage are not cogent. They are emotional, lack logic and embarrassing.
The same is true in economics. The Hannitys of the world repeat “only the rich pay taxes”, which every person with a pay stub knows is not true.
But the biggest mistake of both the left and right is in assuming there are only 2 economic systems: Capitalism and Socialism. So corporatists (Adam Smith called them mercantilists) are called socialists by capitalists and capitalists by socialists. And then we wonder why nobody understands the stimulus, or Federal Reserve or trade policy.
To be cogent, one has to be logical and clear; therefore, flawed logic is absence of cogency by definition.
There is nothing non-cogent with arguments in defense of the free exercise clause of the First Amendment, or in defense of the free market versus government-micromanaged economy.
You appear to be mistaking flowery oration for cogency.