Why is the word "democracy" not in the preamble of the US Constitution?

Another tendency, which is extremely natural to democratic nations and extremely dangerous, is that which leads them to despise and undervalue the rights of private persons.

The republican is the only form of government which is not eternally at open or secret war with the rights of mankind.

To slaves: “You can forget your notions of freedom. We voted fair and square and your side lost.”

What are "demonic attacks" and how can one tell when they're happening to them, or someone else? How would one go about dealing with it?

Meanwhile, when the Democratic Party formed in 1828, it was with a Tory outlook keen on robbing others of their rights:

To blacks: “You can’t drink from that water fountain… eat in this cafeteria… ride this bus… go to this school. We voted fair and square and your side lost.

—Alexis de Tocqueville

Why is Reagan seen as the best president in the USA when he literally destroyed the American economy with trickle down system and was strongly against worker unions?

Why? Try these on for size:

Majority-rules democracy is the way that majorities run roughshod over minorities, destroying rights and all ideas of equality under the law. No fair-minded person wants anything to do with democracy.

In other words, our Founding Fathers and other Whig intellects of that time well understood that democratic methods are the surefire means to do serious damage to the rights guaranteed under republican self-government.

What is your age now, and what age do you prefer to stay at forever?

—John Adams

—Thomas Jefferson

[with republicanism being the rights-protecting form of governance afforded us by our Constitution]

Why do Trump supporters believe Trump should deport the immigrants? These people you call "illegal immigrants" have lived here for many years, they have houses, jobs, how can you think they will just go back to their country, where they have nothing?

When the people find they can vote themselves money, that will herald the end of the republic.

I do not say that democracy has been more pernicious on the whole, and in the long run, than monarchy or aristocracy. Democracy has never been and never can be so durable as aristocracy or monarchy; but while it lasts, it is more bloody than either.

—Benjamin Franklin

Is it common for people to fall in love with someone else while still married? If so, why do they choose to stay in their marriage?

To Indians: “Pack up what belongings you can carry and start walking to Oklahoma. Your fertile lands are ours now. We voted fair and square and your side lost.”