Updated

The fact that the world has been abuzz with Donald Trump's antics since last Thursday night’s presidential debate in Cleveland demonstrates that no one really broke through or was fatally damaged in the debate itself. But what has been largely ignored is how little discussion there was on by far the biggest issue of all: the economy.

The moderators didn’t get around to the topic for an hour, and even then the questions were scattershot.

Yes, Ohio Gov. John Kasich made eloquent reference to the importance of economic growth near the end of the debate and Jeb Bush also mentioned it. But the subject should have been front and center from the get-go.

The candidates should have boldly brought the topic up at the beginning even though the moderators would have objected. There was nothing to stop a candidate from forcefully saying at the start that getting this punk job-creating and personal income-stagnant economy expanding rapidly again was priority No. 1 and then pushing a discussion on how best to achieve this. Instead, the economy came across as just another subject among many.

The big question for the GOP is this: which candidates, if any, will vigorously seize the optimistic, pro-growth mantle of Reagan and make it their centerpiece?

Republicans aspirants should remind themselves of what Bill Clinton's campaign maestro James Carville famously said in 1992: It's the economy, stupid.

Ronald Reagan knew that back in 1980. The Gipper was one of 10 candidates and by far the oldest. Many pundits had written him off after his failed attempt to wrest the Republican nomination in 1976 from President Gerald Ford: the former California governor was stale; he was still reading the same old bromides from cue cards; he would be easily eclipsed by all the new young, vibrant rivals.

But Reagan grasped what his GOP opponents did not: America was hungering for a pro-growth economic optimist.

After stumbling in Iowa where he mistakenly skipped the big pre-caucus debate, Reagan came roaring back in New Hampshire, hammering home in ads and on the stump his support for a radical, 30-percent across-the-board cut in personal income tax rates.

He hit President Jimmy Carter hard for a miserable, inflation-wracked economy, but his message was optimistic: we can get America growing again and here's how we can do it.

To the surprise of political observers, Reagan won a smashing victory in New Hampshire, virtually wrapping up the nomination right then and there. It was this lack of a clarion, up front, radically Reaganesque message of optimism and growth that made this debate, at the end, so disappointing and tepid.

Reagan understood that a weak America meant trouble around the world, not to mention a debilitating malaise at home, and that drastic measures were needed to get the economy soaring again.

He was right, of course. Thanks to his reforms and his determination to kill the terrible inflation afflicting the country, the U.S. quickly roared back; Silicon Valley became the global symbol of cutting-edge technology.

Soviet Union boss Mikhail Gorbachev desperately tried to resuscitate a lumbering, stagnant, bureaucracy-ridden economy — and failed. To the astonishment of all, the Soviet Union collapsed. The U.S. won the Cold War, something virtually every foreign policy expert thought an impossible event in their lifetimes.

We all know the economy today is in bad shape. Most Americans have lower real incomes today than they did in 2007. The recovery from the sharp downturn of 2008-09 is the worst in American history. Which brings up another surprise from that debate: how little the participants hit Barack Obama for this. There were more shots at Hillary Clinton. She should only be referred to as a proxy for an Obama third term.

Attack the Obama economy and couple this with bold proposals on taxes, health care and money. Jeb Bush will stay stalled unless he puts something like the flat tax on the table and trumpets it across the land. His advisers are clearly too cautious. He must show leadership and overrule them. Half-measures or anodyne "a flatter, fairer tax code" sound bites won’t do.

John Kasich must not make the mistake he did Thursday night by leading off with a call for a balanced budget, which most voters take as code for tax increases. Go for the flat tax.

Rand Paul has a very interesting flat tax proposal out there today, but he only mentioned it once — and that in passing — in the debate. Don't bury the best thing you have going for your campaign. Lead with it.

Marco Rubio has offered a substantive tax reform package, but you wouldn't know it from the debate. It needs some tweaks, starting by getting the two tax rates (15 percent and 35 percent, which is too high too generate much growth) down to one. Putting two tax rates together is like putting two rabbits together: they multiply. We should have learned that from the 1986 tax act, where the two rates (15 percent and 28 percent) quickly proliferated. The same applies to Chris Christie's proposal for a three-rate system.

Gov. Walker, Sen. Cruz and Dr. Carson have spoken in favor of the flat tax. It’s time for them to offer up the beef and run with it like Reagan did with his tax-cut plan.

Carly Fiorina has indicated a liking for daring tax reform. A specific plan would dramatically build on momentum she achieved in the Thursday afternoon debate.

Gov. Huckabee mentioned his support of a national sales tax to replace all federal taxes on income only in response to a question on entitlements.

Donald Trump would do his campaign an enormous good by shifting focus to an audacious tax-cut plan.

The big question for the GOP is this: which candidates, if any, will vigorously seize the optimistic, pro-growth mantle of Reagan and make it their centerpiece? I

f none of them do so, the Democrats could well win by default, just as they did in 2012 when Republicans ran a largely substance-free campaign. Even if the GOP should capture the White House, the winner won't have a Reagan-like mandate for big, economy-stimulating policies.