There are two John Cooks in the 1930 US Census who were born in Scotland around 1892. Let's see, the 1930 Census was taken in April, so your John Cook had not had his birthday yet, so his estimated birth year would be 1893. Only one of the candidate John Cooks age matches:
He lives in Clarkstown, Rockland (county), New York. Living on Lenox Avenue.
His native tongue is 'Scotch', Veteran of WWI.
He is a Laborer in a Quarry.
He immigrated in 1903 and has been naturalized (is a US citizen)
Married at age 30 (about the time he immigrated)
Wife: Ella, 26 years old, self and parents born in Pennsylvania.
Son: John M, 1 month (?) old (some scribbles by the age, could
be 1 1/2 over 12)
The other John Cook is married, but his wife is not with him. He is a machinist in an autoworks.
Oh-uh, bad news: found a WWI draft registration for John Major Cook, born 27 Dec 1893 in Scotland. This is probably the one that I just typed in lots of info for.
Oh well, maybe someone else is looking for
that John Cook.