Protecting the Minority

I was very interested to find in Federalist 51, an argument for how the democratic set up would protect minorities.  A few passages to sum it up:

... it is of great importance in the a republic not only to guard the society against the oppression of its rulers, but to guard one part of the society against the injustice of the other part. Different interests necessarily exist in different classes of citizens. If a majority be united by a common interest, the rights if the minority will be insecure. There are but two methods of providing against this evil: the one by a creating a will in the community independent of the majority-that is, of society itself; the other, by comprehending in the society so many separate descriptions of citizens as ill render an unjust combination of a majority of the whole very improbable if not impracticable.

And:

Whilst all authority in it will be derived from and dependent on the society, the society itself will be broken into so many parts, interests and class of citizens, that the rights of individuals, or of the minority, will be in little danger from interested combinations of the majority. In a free government the security for civil rights must be the same as that for religious rights.

In other words, society will have so many different divisions that each one will be afraid to gang up on a different one for fear that they would suffer a similar fate.  This is roughly the history of religious tolerance in England and the low countries.  There were many different flavors and sects of Protestantism and each one was afraid that if only one gained dominance, it would stamp out all the others.  James Madison (who wrote #51) believed that a similar thing would happen in the United States.
Well, it obviously didn't happen in regards to slavery.  Enough parts of society were able to agree on that particular violation, that it persisted until taken apart by war.  But, sadly, the Founders of that time didn't really think of black people as being in the same category as the whites.  So let's acknowledge that big elephant and move on.
As far as I can tell, almost every wave of immigration brought about new bouts of discrimination.  And each of those was overcome in time.  So much so that, things like full blown discrimination against Italians, say, seems kind of wild today.
Full blown protection of minorities came about with the 14th Amendment and the 'equal protection' clause.  It holds that 'no state shall . . . deny to any person with its jurisdiction the equal protection of the laws'.  This has been applied almost exclusively to minorities, which in my lights is a mis-reading.  I think that each individual is a minority of one, and that the law should be read solely in that way.  But what can you do?
Outside of law, there exists a strong and positive attitude in modern western culture that embraces toleration and protections for minorities.  I think that Madison would be very pleased with that.