It cemented President Obama’s legacy as a transformational figure, with the Supreme Court upholding his landmark health care law and ratifying the right to gay marriage. The President’s powerful eulogy at the Emmanuel A.M.E. church in Charleston, which you can watch here, demonstrated that he has entered a new phase of his leadership, self-described as “fearless”. Earlier this year, we left the President off Fortune’s World’s Greatest Leaders list, because of his failure to mend the broken politics of Washington and his uncertain hand in foreign affairs. But while Obama isn’t LBJ or FDR, he emerged last week as a different sort of leader, with a unique ability to speak to us as nation about our deepest wounds. (James Fallows of The Atlantic does a brilliant dissection of the speech here.)

It was also an important week for business. The passage of Trade Promotion Authority was a critical win, and the health care decision brought much-needed certainty to that industry. Even more notable was the leadership role that companies like Walmart, Amazon and eBay played in the confederate flag debate, and that a much broader coalition of companies, again including Walmart, played over the past decade in providing benefits to gay couples.

In the wake of last week’s developments, some also called on Walmart to ban the sale of guns. That’s understandable, but a step too far. Americans remain evenly split on the morality of gun ownership, with as many concerned about protecting gun rights as are concerned about gun control. Big business can’t – and shouldn’t – be expected to take positions opposed by such large portions of their customers, employees, and the communities in which they operate. Walmart could consider, however, using its supply chain clout to insist on safer guns – as suggested by Roger Parloff’s excellent piece in our May issue: “Smart Guns: They’re Ready, Are We?”

Big business may never be the vanguard of social change. But as last week shows, it can play an important role in encouraging needed change when politicians remain captives of the extremes.

This week, attention turns to Greece.

Top News

• Greece shutters its banks

Greece is closing its banks this week and imposing capital controls after the European Central Bank refused to increase an emergency credit line to cover a stampede for cash by panicked savers. In the short term, the move threatens global markets but the big picture suggests that the European Union is a step closer to reversing an integration process that has spanned over 60 years.  Fortune

• Puerto Rico's debts "not payable"

Though Greece gets a lot of the attention for its credit line woes, Puerto Rico is also running into some major problems. The island's governor has concluded Puerto Rico cannot pay its roughly $72 billion in debts and indicated his team will seek "significant" concessions from as many as all of the island's creditors. Alejandro García Padilla says his statements are a reflection of math, not politics.  New York Times (subscription required)

• SpaceX rocket explodes

A rocket launched by entrepreneur Elon Musk's Space Exploration Technologies that was taking supplies to the International Space Station exploded just a few minutes after it took off in Florida on Sunday morning. This launch was to have been Musk’s third attempt to land the first-stage booster safely on a barge in the Atlantic ocean, after two earlier attempts failed to do so.  Fortune

• Chinese stocks tumble

"Nobody knows when the market will bottom," says one Hong Kong-based chief investment officer, regarding the turn in trading that sent China's benchmark index into a bear market. The retreat has marked an end to the country's longest-ever bull market, a rally that successfully lured new individual investors. But China's interest-rate cut has failed to stop the rout, and regulators are even mulling the suspension of IPOs until the nation's stock markets are stabilized.  Bloomberg

Around the Water Cooler

• The king of Amazon's cloud

Google researchers have built a system that can analyze existing conversations from a massive collection of old movie dialogue — and teach itself to respond. While the system currently under development is merely proof of concept, it could eventually be used to improve online chatbots that help answer technical support calls. And as Wired points out, the machine is eerily good at debating heavy topics like the meaning of life.  Wired

• Why fur is back in fashion

Fur, it seems, is in vogue again. Sales of the controversial garment appear to be humming nicely lately, with a new crop of young designers increasing use of the material in their creations. Sales are being driven by two groups: older clients looking for a high-end gift and younger professional women who want to splurge. Mother Nature can also be thanked, as it appears record cold temperatures in the U.S. the past two winters were also a tailwind.  Fortune

5 things to watch for this week

Greece’s drama, jobs, and holiday travel — 5 things to watch for this week. This week's story can be found here.