The Semantics/Philosophy Chat (as started by Yip): Loyalty versus Fidelity

A few months ago, a good friend of mine, Yip, posted the following question: 

What's the difference between between loyalty and fidelity?

Of course, being the equable wise-man that he is, Yip had already an answer for the question and, surely, was only looking for the joyful semantic, or most probably philosophical, argument. Having the sweet tooth for semantics, as it is way simpler than philosophy, I dared to bring my piece into the conversation. 

Caveat emptor: These are my sole musings without referring to a classical source. In other words, most probably, this is completely useless. 

In Spanish, the words are easier to distinguish than in English: Lealtad versus Fidelidad. They come straight from the Latin, the first from Legalitas and the second from Fidelitas, which derive from Lex and Fides; law and faith, respectively. Law is usually derived from a social covenant which all parts abide by good-will and, not necessarily but ideally, towards the common-good, while faith is derived from a sacred covenant. I would say that, for practical purposes, the first is based either on respect or, in the worst case, balanced retribution, read fear, while the second is fiduciary, that is, it is  based on trust/faith, I would even go as far to say that it is independent of the object of trust/faith, as in one way blind observance that comes with religious faith—I, the polarized autistic that I am, usually restrict my common use of fidelity/faithfulness to religious/absolute-truth matters only.

Of course, after the exchange, a second question came from my noble friend,

Who or What's to be the object of Loyalty or Fidelity?

I was fearing this one. In English it is quite simple, Fidelity is mostly used as the degree of exactness in a copy, and the equivalent Faithfulness is only used in the context of religious faith or marriage. On the other hand, Loyalty is used to express trust on someone or something ranging from nation to a brand. The same can be said in Spanish. So, my fear was not from this exact question, as the uses are clearly distinguished, but from the implications of Loyalty.

My problem comes from this. It is hard for me to understand even the simplest concept: Loyalty to a sovereign nation. I understand it (loyalty to a sovereign nation, in my case México and the country I live/work at the time) as abiding to the social contract trusting that it will be fulfilled by good-will or, else, enforced by the institutions of such society. My problem is that I cannot conceive loyalty as being born from fear of the law. I have the feeling that loyalty obeys a lex talionis, as does respect and trust; that is, a retribution law where loyalty/respect/trust is given in exchange of loyalty/respect/trust. I believe—I use the word believe because I cannot prove it—that loyalty out of fear is as fleeting as infatuation was in my high school days.

So, what do you think? Is loyalty tied to trust or respect? Can it be born from fear or, in my opinion, even worse, bought? I cannot foresee many implications, the ones I can see come in the form of the past dictatorial rule, mainly leading to world war the second, where common-good—a false common-good so far—is imposed rather than worked out. Sadly, that seems to be always the case in human society; with the possible exception of modern times Nordic countries and Germany where economic development has been supported upon the development of human rights.

As a side-note, I am a sucker for good-will and philosophy since someone—most probably one of my aunts—read to a young, easily impressed version of me this phrase attributed to  Aristotle: "I have gained this by philosophy: That I do without being commanded what others do from fear of the law"—it was later chiselled into the rock inside my head by continuously playing civilization ever since my college days; one thing is for sure,  it was the leading factor behind my reading of philosophy books in my aunt's library, and the continuous debate with the Jesuit seminary students that taught the social action classes in high school, but that's another story—.