Narrated Ibn Umar: We did not become full after eating until we conquered Khaybar.
The estates of Fadak and Khaybar played a crucial role in providing financial stability for the Islamic State. The wealth generated from these lands was so significant that the Prophet (saw) used it to fund military expenditures, which are typically the largest area of government spending. This highlights the immense economic value of Fadak.
Abu Bakr al-Jawahri records the words of Abu Bakr when he confiscates it from Fatima (as) in his Kitab al-Saqifa wal-Fadak, pg. 192 - 193:
وإنما كان مالا من أموال المسلمين يحمل النبي به الرجال وينفقه في سبيل الله
It (i.e. Fadak) was, in fact, wealth from the Muslims, which the Prophet (saw) used to equip men and spend in the way of Allah.
Alkarbala