It's just a national symbol; most countries have something similar. Also, the US nuclear weapon stockpile is down to about 5,000; hasn't been 30,000 since the 1960s.
I won't bother to look up the current number: 5,000 is scarry enough, but I stand corrected. On the other hand, do you have a reference to a list of similar menacing national symbols?
The eagle isn't doing anything especially menacing like the British lion is. It holds arrows to represent preparedness for war, but also an olive branch to represent preference for peace. I'm not familiar with the symbolic meaning of the elements of the British Royal Coat of Arms: does it contain any equivalent to the American olive branch?
Not exactly an expert on heraldry, but I'm fairly fascinated by it.
The British Royal Coat of Arms, which is the say the coat of arms of the Royal family does not have anything equivalent to olive branch. Rather, it's a coat of arms to depict the 'linage' of the United Kingdom. The triple lion represents England and is form Richard the Lionheart's Coat of Arms, the single lion represents the Scottish crown, and then harp Ireland.
Remember, coat of arms were originally meant to be more or less unique identifiers for armored noble men. The British (and many other European coat of arms) are direct results of centuries of Royal Families merging, changing, redesigning their heraldry. Their message/symbolism can be 'constructed' as much as history allowed them to be. The Great Seal (and coat of arms) of the United States was designed. A few people sat around and decided what to put on it and what it would represent. The closest to that happening in 'old Europe' would be the royalty trying to figure out which third cousin (only half joking) to marry, or what land to invade and exactly which method to use to join the coat of arms.
Seriously, I think that in heraldry is interesting stuff. An attempt at a system that codifies a which relationship between visual and written display. In case you never knew, every piece of heraldry has a written description that describes the piece of heraldry 'precisely'. That is to say that if you follow the rules, then any drawing that satisfies "Or a lion rampant within a double tressure flory-counter-flory Gules" (Scotland) -is- the Scottish coat of arms (in theory anyways). For example "Or a lion rampant" means golden lion in the rampant position. Doesn't matter how you draw the lion, as long as its recognizable as a lion.
A roaring lion rampant is supposed to be menacing, but the British lion is a bit disney cartoonish. I don't know the symbolic meaning of the components of the coat of arms - it seems to have been through a lot of revisions: http://en.wikipedia.org/wiki/Royal_coat_of_arms_of_the_Unite...
