"Smokey, this is not 'Nam. This is bowling. There are rules."
— Walter Sobchak
Smokey This Is Not Nam This
Smokey, this is not 'Nam. This is bowling. There are rules.
About this quote
The fuller version of Walter's bowling-lane outburst in The Big Lebowski (1998), directed by Joel Coen. Walter addresses his teammate Smokey by name before launching into his rule-enforcement lecture, making explicit the contrast between the trivial setting — a bowling alley — and the outsized moral urgency Walter brings to everything. The phrase "This is not 'Nam" became a popular cultural reference.
Source
The Big Lebowski (1998)