The project is a "good deal" for the state economy, he told ABC News' Jonathan Karl on "This Week," and he insisted that it is "not a new tax."
"We would lose $419 million over the next 20 years if we did nothing, if we said, go on, move somewhere else, which the NBA said they would do," Walker continued. "In this case, we don't raise any taxes. There are no new taxes, only existing taxes. And we get a three to one return."
The project will be funded by existing taxes on hotel rooms and rental cars, though the Wisconsin Center Board has the authority to raise the rate, he said.
"In this case, we take the tax, the revenues on hotels and rental cars that are currently paid for the convention center and allow those to continue to be paid for a new arena," Walker said. "It's not a new tax."
"All across the nation when they do projects like this," Walker said. "It's a good deal."