Eric Schmidt took the stage Tuesday evening in Barcelona to address a sometimes-hostile crowd. His message? Mobile comes first, and Google "comes in peace."Google has been pushing further and further into the mobile world the last few years. It started by offering up mobile optimized versions of its Web services, such as search, Gmail, Maps and so on. Then came its tight integration with Apple's iPhone. Then Android ... and the eventual dozens of handsets that have flooded the market to compete with the iPhone. Then a mobile social networking service. Then an announced broadband offering.

People are beginning to wonder just what type of business Google thinks it is, because, well, its intruding on the business of so many other businesses.

That was obviously going through the minds of Schmidt's audience Tuesday night, which put the Google CEO on the hot seat about a number of issues. One attendee accused Google of pushing the network operators into becoming "dumb pipes". Schmidt bristled at the idea.

"I disagree with your premise completely," he said. "In the first place, I feel very, very strongly that we depend on the successful businesses of the operators globally, and I disagree with you that quote 'we're trying to turn the operators into a dumb pipe.'"

When picked on over Google's stance on network capacity and net neutrality issues, he said, "It's important for operators to be able to deal with too much capacity and misuse of the networks because we understand at a fundamental level that wireless networks have constraints on them. The only specific issue we have is that we don't want operators to choose between different vendors of the same kind of content."

Schmidt wasn't on the defensive the entire night. Before the Q&A session, he gave the standard Google boilerplate talk about Google's current focuses. He noted that Google developers are more excited about creating products and services for mobile than for the desktop. "We understand that the new rule is mobile first. Mobile first in everything. Mobile first in terms of applications. Most first in terms of the way people use things. And it means that we have a role now to inform, to educate through all these devices."

Schmidt also took some time to show off a few new services headed to mobile. Google is rolling out a new Labs feature for its Goggles search product. It uses optical character recognition to recognize the text within a photo. It can then translate that text into another language and return the results to end users instantly. Schmidt also said that it is soon going to offer Google Earth to the Android platform. So far, it has only been available to the iPhone.

If you missed the live Webcast of Google CEO Eric Schmidt's keynote at the Mobile World Congress event in Barcelona, excerpts are available in the video below.