"It was the best of times, it was the worst of times." That well-known phrase was penned by Charles Dickens more than 150 years ago, but it's just as relevant now. And while Dickens wasn't talking about privacy, he could have been, said Microsoft's Brad Smith as he opened his keynote speech at the IAPP's Global Privacy Summit here in Washington yesterday. 

That's because the big data society is generating and the proliferation of technology innovating the ways we use it means big advances and opportunities ahead. It means agriculture shifts because with cheap sensors and data it's now possible to grow plants using 90 percent less water. It means, using the cloud and a cellphone, the 2 billion people around the world who historically haven't had access to banking suddenly have it. 

But there's a danger in that. The data we're generating is becoming increasingly sensitive. That was evident in the 2014 Sony hack, allegedly sponsored by North Korea; and the attacks in San Bernardino and Paris. The incidents led to increasing questions by the public and governments about encryption and surveillance. Smith said he doesn't go anywhere these days without someone asking him about his position on the FBI v. Apple case, in which the government wanted Apple to unlock its phone for access to data in the name of fighting crime. 

"All these issues and events call on us to ask one fundamental question," Smith said. "What do we need to stand for?" 

For different companies, that will mean different things. But every kind of business and culture can surely agree on the idea that "we will continue to keep people safe," he said. And that's why, when the explosions started in the Brussels airport two weeks ago and the police went to Microsoft with 14 lawful orders for information, Microsoft complied with an average turnaround time of 30 minutes. 

But practicing that kind of data stewardship, which comes in handy when the police really need it to potentially save lives, requires vigilance.

"If we're going to keep people safe, we also need to keep the information secure," he said. 

In the Apple v. FBI case, Microsoft publicly sided with Apple. But the Apple case is just one piece of a much larger conflict regarding what kind of access the government should have to private companies' data. 

Smith said transparency is key in this fight. Microsoft was one of several companies who sued the U.S. government in 2013, arguing it had a constitutional right to share information with the public about national security orders it receives. In 2014, it challenged a subpoena from the FBI that sought content from an enterprise client. 

"It was and remains our view that when the government wants content that belongs to the enterprise, it should go to the enterprise, not the cloud service provider. It should give the enterprise itself the chance to look at the order and decide if it wants to comply or go to court," he said. 

Microsoft has also filed a suit to fight the government's request for access to emails Microsoft stores in Ireland, arguing that granting the request would result in the government basically being able to get access to any email anywhere in the world, regardless of its location. 

"That, in our view, simply goes too far," Smith said. 

It's important to remember, he added, that only 4.5 percent of the world's population lives in the U.S. 

"We have a responsibility to the world," he said. "Even if we don't always agree with everything, it's important we understand where people are coming from." It was important, for example, when the European court struck down Safe Harbor to listen to the reasons why and where those critical voices were coming from. 

So what needs to happen in the future for tech companies to continue to innovate and for data to continue to change the world for the better? 

"We need good law," Smith said. The law must be modernized to move tech forward and companies must practice what they preach. 

Privacy isn't just an issue, he said: "Privacy is a cause. It is a cause worth embracing."