Watch out for claims that government spending would "pay for itself".
In some cases that's true, but the companies that would get the money
will try hard to exaggerate the public savings that would supposedly
result. Thus, most of these claims are
bogus.
Those arguments are harmful at a deeper level. They inculcate the
idea that state's highest priority is to reduce its budget deficit, so
it should fund whatever activities will have that effect.
However, if the state considers funding something inessential
specifically to make a profit, that shows it's not one of the state's
important functions — because those must be done, even
though they cost money.
The very idea of insisting on a balanced budget for the state is
foolish, since that policy tends to turn any recession into a
depression.