The keyword phrase is a composite proper noun or a noun phrase. The core component and main subject is the proper noun "Sardar Vallabhbhai Patel," identifying a specific individual. The date "11 sep 1948" acts as a temporal modifier, functioning adjectivally to specify a precise moment related to the subject. The primary part of speech, therefore, is a noun, establishing the person as the central focus.
This date marks a critical point immediately preceding the launch of Operation Polo, the Indian military action to annex the princely state of Hyderabad. As India's Deputy Prime Minister and Home Minister, Sardar Patel was the chief architect of this operation. On September 9, 1948, he gave the final authorization for military intervention to counter the secessionist ambitions of Hyderabad's Nizam and the atrocities of the Razakars. The date of September 11, 1948, falls within the final 48-hour window of mobilization and strategic preparation before the Indian Army entered Hyderabad on September 13, 1948.
Analyzing the phrase grammatically establishes the article's focus: the decisive agency of an individual at a specific historical juncture. The noun "Sardar Vallabhbhai Patel" anchors the narrative to his leadership and statesmanship, while the date highlights the imminence of a defining event in the integration of India. The combination signifies Patel's pivotal role in authorizing the police action against Hyderabad, a culmination of his policy to unify the newly independent nation.
