The Garmin-Sharp rider retained the race leader's yellow jersey, flying the flag for a new generation of US rider after Lance Armstrong and several of his own teammates confessed to doping.
"I think we're all motivated after what happened this winter in US cycling. We've got a lot to prove. We want to prove that we love this sport and that we're committed to bringing it out of the ashes of the past," Phinney told Cyclingnews.
"It's a really important year for American cycling and already with Brent Bookwalter wining in Qatar, a couple of us there in GC and now Andrew Talansky and Tejay [van Garderen] performing really well in Paris-Nice, it's great. The time to strike and rebuild the image of cycling is now."
Armstrong often bullied his fellow US riders, putting pressure on them to work with Dr. Ferrari and follow his lead when it came to taking EPO and blood doping.
Phinney indicated that the current generation of US riders is much more united as a group.
"With the riders we have, we encompass every aspect of the sport, whether it's climbing with Tejay and Andrew, or time trials with me or sprinting with Tyler Farrar. It's a testament to US cycling and our motivation as a group to build on the foundations that have been left in shambles," he said.
"I'm really happy with what's going on and that we're a unified group despite riding for different teams. It's good we're doing a kick-ass job."
Phinney is part of a powerful BMC Racing Team at Tirreno-Adriatico, with Armstrong's former directeur sportif and now BMC team manager Jim Ochowicz also at the Italian race.
BMC finished third in the opening team time trial on Wednesday and Phinney was 17th on stage two to Indicatore. His big goal is the final 9.2km individual time trial next Tuesday.
"My main job is to help Thor Hushovd in the sprints and then stay fresh for the final time trial," he said. "I hope I can have a big battle with Tony Martin and Fabian Cancellara."