Twitter's recently announced capability to filter out tweets on a country-by-country basis is not a means of proactively censoring content, CEO Dick Costolo said on Monday evening at the "Dive Into Media" conference hosted by All Things D.

The micro-blogging site garnered backlash from users last week over the announcement that it is now able to block tweets that run afoul of certain countries' restrictions on speech. The new policy will simply allow the company to transparently deal with valid government requests to remove certain content, Costolo said.

"This is purely a reactive capability, we don't proactively go do anything," he said.

When the company is issued a legal takedown order, it will now be able to withhold that content from users in that specific country, while keeping it available to others.

"There has been no change in our stance or attitude or policy with respect to content on Twitter," Costolo said. He added that Twitter believes "this is the most honest, transparent, and forward-looking way for a company to deal with the myriad of complex issues around the world that you experience when you have to operate in these countries."

Twitter needs to have such a policy to operate in certain countries, Costolo said. The move is not an attempt, however, to expand Twitter into China, where the social media site is currently blocked.

"I don't think the current environment in China is one which we think we could operate," he said. "We would love for people in China to be able to use Twitter the way we want them to be able to use it, which is speaking freely and letting their voices to be heard by as many people around the world as possible, we would love that."

During the interview, Costolo also touched on a range of other topics, including the company's stance on a future initial public offering and Twitter's role in the 2012 election.

"I really think 2012 is going to be the Twitter election," he said.

Almost all the Republican presidential candidates have used Twitter's suite of advertising products. Lawmakers are also actively engaging in a "real-time feedback loop" on the site. And during President Obama's State of the Union address, there was a "collective groan" on Twitter when he made a joke about spilled milk.

"Candidates that don't participate on Twitter while the conversation is happening will be left behind," Costolo said. "Tomorrow morning will be too late to react to what was said the day before."

Meanwhile, he added that it will be "fascinating" to see if Facebook files papers for an initial public offering this week, as it is expected to do, but Twitter is focusing on its own goals, not what its rival is doing.

"We are going to be really patient about the way we build the business," he said. "We are trying to build a decades-long, lasting business."

Costolo hinted that Twitter will also likely need to go public at some point, but said he is not worrying about that right now. Asked directly whether there is going to be an IPO for Twitter in the future, Costolo went quiet for several seconds before saying "I choose not to answer that question."

For more, see Before Facebook: A Look Back at Major Tech IPOs.