Modern banking began with a war. More than 700 years ago, the Republic of Venice fell short of funds during a military conflict. They borrowed money at 4 per cent interest from a hastily created organisation known as the Chamber of Loans.
This fledgling body began taking deposits from Venetian merchants and lending the money onward. Modern banking was born.
Other cities in Europe - Genoa, Barcelona, Amsterdam, Hamburg - gradually followed. These banks fuelled the rise of Europe to global economic dominance. Indeed, it can be argued that Europe's eclipse of the Middle East from the 15th century onward owed much to two inventions: gunpowder and banks.
Eventually, banking swept the world, and it is hard to imagine today's global prosperity without banks. Lines of finance and credit from banks have built our global infrastructure, fuelled innovation, spurred the trade revolution and supported life-saving technological breakthroughs.
That's why the state of banks today is so troubling.
Yes, banks continue to fuel growth, support commerce and trade, and undergird the globalisation that has brought undoubted benefits to our world. But over the past decade, banks have lost their most important currency: trust. And the events of the past week have exacerbated the trust gap.
Let's start with "the Whale". That was the nickname of Bruno Iksil, a London-based trader with JP Morgan Chase, whose bets were so large that they moved markets. Eventual Mr Iksil beached: it turns out that JP Morgan Chase could be facing $7 billion (Dh25.7 billion) in losses from three London traders including him.
Of course, that's the nature of trading: you can win big, or lose big. The real problem, it seems, is that "the Whale" and associates sought to hide their losses.
The firm is coming clean, but the loss is particularly troubling because its chairman and chief executive officer, Jamie Dimon, emerged from the 2008 banking crisis as "the adult in the room" - the careful, sober banker who was not part of the reckless leverage and risk-taking culture that had taken hold in Wall Street.
Another US banker, too, has had a rough month: Bob Diamond, former CEO of the British institution Barclays, the fourth-largest bank in the world. Mr Diamond was swept out of his post unceremoniously amid a scandal over endemic manipulation of the Libor rate - the interest rate at which banks lend to each other.
It turns out Barclays sought to keep the Libor rate artificially high when it suited them, and to lower it when it suited them - that is, to inflate their own profits, at the expense of customers and millions of others. In effect, they distorted a vital interest rate market used by banks worldwide.
For that transgression, Barclays paid a $453 million fine, lost the trust of its customers and widened the trust gap between the public and banks in general.
The Libor scandal does not end with Barclays. The settlement the UK Commodities Futures Trading Commission reached with Barclays makes it clear that at least three other banks were complicit as well. Indeed, nearly all of the 17 banks that participate in Libor are under investigation.
The financial services industry took another heavy blow this week in a breathtaking case of blatant fraud. The founder and president of Peregrine Financial Group, a financial futures brokerage, admitted to embezzling more than $100 million from clients over nearly 20 years. Although the amount is much smaller, the action recalls Bernie Madoff's siphoned billions.
Meanwhile, across Europe, banks continue to suffer under the weight of debt loads built up in years of reckless lending and over-leverage. Bank weakness in southern Europe will continue to plague eurozone recovery efforts.
Banks in the UAE and across the GCC bought into the reckless, risk-taking culture. Abdul Aziz Al Ghurair, the chairman of Mashreq Bank and new chairman of the DIFC Authority, told Gulf Business magazine in a frank interview: "There was so much pressure on banks to grow, grow and grow. They compromised on their basic lending philosophy, we lost sight of some things."
The always-sensible Martin Wolf of the Financial Times reminds us that "the days when the local bank manager was almost as respected as the doctor have long gone. We are never going to turn bankers into saints". But, as Wolf notes: "We can change the incentives facing bankers, the structure of banking and the focus of regulation. Where I would go further is towards substantially lower leverage and significantly greater transparency."
These two ideas would a be a good start. A war in Venice launched modern banking. Regulation will play a critical role, but the war for the future of this vital institution needs to be fought in boardrooms.
Banking leaders must understand that their most valuable currency - trust - has depreciated sharply.
Afshin Molavi is a senior adviser at Oxford Analytica and a senior fellow at the New America Foundation in Washington DC
On Twitter: @afshinmolavi