Meghan Agosta, on the power play, and Sarah Nurse provided the scoring for Canada, with second-period goals just over seven minutes apart.
Team Canada hockey defeated the team of Switzerland in the match of the tournament of the Olympics-2018 in Pyeongchang. With Megan Keller in the box for interfering with Poulin, Natalie Spooner in her 100th global game spun and hit Agosta in the slot with a backhanded pass. Agosta's shot went off goalie Maddie Rooney's glove and in for the goal.
Finland and the Russian team will play quarter-final games Saturday against Switzerland and Sweden.
One of the most storied rivalries in sport has only heated up in recent years.
Natalie Spooner, playing in her 100th game for Team Canada, made a no-look backhand pass to set up Agosta at 7:18 of the first period to give the Canadians a 1-0 advantage.
On that Bourque goal, some good work from Derek Roy in the corner to win the puck back before feeding the point to Lee (Roy picks up a primary assist).
Irwin was also called for closing her hand on the puck in a goal-mouth scramble at 16:08 of the second. That carried over until late into the second period when Nurse fooled US goalie Maddie Rooney with a top shelf shot instead of going for a pass across to her two teammates that entered the zone with her. Not surprisingly, a scuffle broke out because, well, it's U.S.
Nurse's wrist shot off Rooney's right shoulder deflected into the top of the net at 14:56 of the second.
"Those are the fun ones", usa forward Amanda Kessel said. The U.S. outshot Canada 45-23, but failed to capitalize on a late power play that could have tied the game. Lacasse stoned an all-alone Hilary Knight four minutes after faceoff.
Canada went 5-1 against the Americans in a six-game exhibition series this winter, although the US beat Canada twice to win November's Four Nations Cup tournament in Florida. Wolski's pair of goals during Canada's opening game helped defeat the Swiss 5-1.
The Canadian women won Pool A with a 3-0 record and advanced to the semifinal on Monday.
Slovakia is next, in a game that starts at 10:10 p.m. ET on Thursday.
Canadian head coach Laura Schuler played all three goaltenders in the preliminary round.
When Amanda Kessel came back from her first Winter Olympics in Sochi, Russia, she was forced to carry two burdens that would define the next four years: a silver medal and concussion symptoms. Veteran netminder Shannon Szabados had 22 saves in Canada's 4-1 win over Finland on Tuesday.
What would have been one of the hottest tickets at any of the five previous Olympics featuring a Canadian team loaded with National Hockey League stars playing in their tournament opener was treated with disinterest as the world's best players sat these Games out.
The Canadian women have had puck drops at 9:10 p.m. and 4:40 p.m. and Thursday's game started just after noon local time.
Canada forward Jillian Saulnier said they try to represent the best of women's hockey anytime they step on the ice.