In the keyword phrase "september 11th attacks year," the main point or head of the phrase is the noun "year." The preceding component, "september 11th attacks," is a proper noun phrase that functions as a noun adjunct. A noun adjunct, also known as an attributive noun, is a noun that acts as an adjective to modify another noun.
Grammatically, the structure places emphasis on the "year" as the central subject. The phrase "september 11th attacks" serves to specify exactly which year is being discussed. This is analogous to phrases like "kitchen table" or "business meeting," where "kitchen" and "business" are nouns that modify "table" and "meeting," respectively. Therefore, while "september 11th attacks" is a noun in its own right, its role within this specific construction is adjectival, providing a defining characteristic for the noun "year."
This analysis is crucial because it dictates the focus of the article. The primary subject is the year itself (2001), examined through the lens of the September 11th attacks. The content should revolve around the concept of that specific year as a temporal entity, defined and forever altered by the event. The grammatical structure signals that the article's scope is the year as a whole, with the attacks serving as the central, defining event of that period.