Our national anthem is linked to world history.
The Spanish colonial empire collapsed in two stages. The first stage was at the end of the Napoleonic Wars, with countries in mainland Latin America gaining their independence from Spanish rule. The second stage was in 1898 and involved the Philippines.
The Congress of Vienna in 1815, which ended the Napoleonic Wars, was predicated on the restoration of dynastic rule - meaning, the restoration of Spanish rule in Latin America. Thus, our Latino cousins were confronted with the possibility of a reconquista by the Spaniards. This explains why the national anthems of most Latino countries contain pledges to fight or die for la patria y libertad.
Enter US President James Monroe with his Monroe Doctrine, which stated that any attempt by European powers to reestablish colonies in America will not be tolerated by the United States. This doctrine prevented the restoration of Spanish rule in Latin America. Thus, our Latino cousins managed to maintain their independence.
In 1898, the second phase of the collapse of the Spanish empire took place. These involved the islands consisting mainly of the Philippines, Cuba and Guam, which exited the Spanish empire at this time. And, as in 1815, American intervention again prevented a reconquista of these islands.
Our nationalist historians, in a revision of history, depicted the First Republic as a viable sovereign entity if the United States had not intervened in the Philippines. Actually, without US intervention, Spain had the means to cause trouble to our First Republic. Although the army of our First Republic had seized major portions of Luzon, we did not have a navy. Spain still had a navy that could have blockaded the Philippines and dismembered our country by isolating the Visayas and Mindanao from Luzon.
Thus, like our Latino cousins, we were faced with a Spanish reconquista in 1898. This danger, in common with that faced by Latino countries in 1815, explains why our national anthem is a mirror image of the anthems of our Latino cousins. They are products of the same historical process, which is the collapse of the Spanish empire and the danger of the restoration of Spanish rule.
To cite an example, the last lines of the anthem of Guatemala are a clone of our anthem. (The anthems of all United Nations members are in the UN website.)
Because of the Monroe Doctrine, our Latino cousins never faced the danger of foreign invasion. However, the lines in their anthems about defending la patria y libertad remained relevant because of the threat of tyranny imposed by their local caudillos. This is where we differ from them. We had to face Japanese imperialism in World War II, and are now faced with the Chinese threat of hegemony in our region.
Consequently, the last two lines of our national anthem not only honor our countrymen who resisted foreign rule, right up to the Japanese invaders in World War II; in time, they have also become a fitting tribute to our countrymen who died resisting the tyrannical rule of the dictator
Thus, our anthem should remain as is, so as not to detach it from the historical events on which it is based. In addition, at some future time, we may have to again invoke our anthem against another local tyrant. This is an ever-present danger to our republic.