SQLite accepts non-existent foreign keys?

While following the official guideline for using foreign keys on the SQLite homepage, I discovered that the outcome is not what I expected. After creating the the corresponding tables:

CREATE TABLE artist(
  artistid    INTEGER PRIMARY KEY, 
  artistname  TEXT
);
CREATE TABLE track(
  trackid     INTEGER, 
  trackname   TEXT, 
  trackartist INTEGER,
  FOREIGN KEY(trackartist) REFERENCES artist(artistid)
);

…and then inserting the exact corresponding data as shown in the tutorial, running the following query:

INSERT INTO track VALUES(14, 'Mr. Bojangles', 3);

…is accepted when I run it, contrary to what the guideline says. I have seen this behavior in other (similar) SQL scripts that I have written, so this guideline description shows fairly well other confusions I have had. Am I missing something? Thanks.