The barriers that have long blocked Pot Inc. from access to banking services may soon crumble, setting the stage for exponential growth in the $50 billion cannabis business, On The Money has learned.

At this point, the key barrier is GOP opposition — mainly in the US Senate — to legislation known as the SAFER Banking Act that would create a “safe harbor” for marijuana, meaning big banks can finally lend money to any business that touches weed.

But wait a minute, isn’t pot in its various forms — from joints, to gummies to gels and ointments — already legal in just about every state and recently, after President Trump’s executive order in December , also OK in the eyes of the federal government?

Tim Scott, the GOP senator from South Carolina and chairman of the Senate Banking Committee, suggested the opposition – including his own – may be waning. Jack Forbes / NY Post Design

That, it turns out, is a complicated question. True, most states have decriminalized weed, and some have made it 100% legal.…