I was delighted to see that there is a well-followed, well-written Irish monarchist blog (which I discovered through linking to a site that links to THIS site).
Chesterton was not a fan of monarchy. In one article on the death of King George V (I'm too lazy to find the reference right now), he said that monarchism was perhaps the most democratic form of government after pure democracy, since the lottery of succession stood a better chance of throwing up an ordinary man than the rule of cabals and cliques. But this is the most favourable reference to monarchism I have been able to find in his work. Most of the time he insisted that democracy was the primordial form of human assocation, and that monarchy was a late-comer, a degeneration; I find this dubious as well as irrelevant. (Why should the first be the best, anyway?)
Personally, I am a monarchist to the bone, and Chesterton's lack of enthusiasm for the institution has always grieved me. I think monarchy is important because it preserves a living link with a nation's past and traditions; because the head of state should be above politics, and above the slings and arrows of invective. A man is born under a monarch, and he owes him unconditional homage; it is good for men to have a loyalty which is not negotiable, and from which they derive no benefit. (Actually, I believe they do derive benefit from being the subject of a monarch, but it cannot be reckoned in monetary or practical terms.)
The chap (I guess it's a chap, though I don't know) who writes Irish Monarchist chooses to remain anonymous, since anti-monarchism is so strong in his home of Northern Ireland. I understand his reticence. I myself sometimes feel bad insisting that I am a patriot but NOT a republican, since so many brave Irish men and women died explicitly for republicanism. But I believe that republicanism, being an atomising and ahistorical philosophy, must inevitably be antagonistic to the very idea of a nation.