What “Lady Bird” taught me about teenage dreams and ambition

What “Lady Bird” taught me about teenage dreams and ambition

In the opening scene of Greta Gerwig’s “Lady Bird,” Saoirse Ronan (“Little Women”) delivers the knock-out line: “I wish I could live through something.” It’s a sidebar to start an argument, an offhand, quiet remark to which her mother (Laurie Metcalf, “Roseanne”) simply replies: “Aren’t you?”  It’s almost ridiculous. She’s enduring 2002, living through a lot — the aftermath of a national tragedy, the excitement and horror at the new millennium —…