Why is the parliamentary system so popular?

Well, of course, that’s more-or-less why the US has the system that it does. The President is analogous to the king - head of state, not elected by or accountable to Congress, able to appoint the heads of government agencies, but not able to get much done unless he can persuade Congress to pass the legislation he wants, and to accept his appointments to great offices of state. The big change was to make the president elected by the electoral college, and holding office for a limited term.

Because the king didn’t have that mandate, as democratic ideas took hold in Europe european monarchies evolved, with more and more real power passing to prime ministers/chancellors/what you will who were more and more dependent on parliamentary support, and less and less residual power in the hands of the monarch. This happened at different rates in different countries, of course, but the overall trend towards monarchs becoming more and more constitutional, or simply being abolished in favour of more-or-less ceremonial presidencies, is pretty clear.

The US, as an early adopter, gave their head of state/government the authority of a a democratic mandate early on, and so he was able to resist the trend towards making the executive accountable to a parliament. (That, plus the early adoption of a written constitution which crystallised the relationship, and which is difficult to change.) Hence the “imperial presidency” - the US president still having powers and a role broadly analogous to those of an 18th century British monarch.

My (too long) post having been eaten, here’s a short (*) version about the way France ended up with a parliamentary system in the 19th century.

After the fall of Napoleon III in 1870, the country was politically divided, and in fact the royalists held a majority. Their main problem was that they were divided between two potential pretenders, and the most legitimate of both was unsuitable to become king due to his unrealistic exigences. So, basically they decided to wait until his death, and since he had no children, this would have resulted in only one contender, an a more reasonnable one. Meanwhile, the legislature tiptoed, for instance not naming the head of state “president” to keep all options open.

Unfortunately, the old chap turned out to be unwilling to die quickly, and eventually, the royalists lost their majority never to get it again.

This having lasted quite a long time, a constitution had been adopted, and various manoeuvering had resulted in the head of state being called president. France was firmly republican. The constitution granted extensive powers to the president. So, no problem, right?
Not so. In fact, it had never been clearly decided whether those powers were theorical or real. The two first heads of state had been complete opposite. The first one (not yet named “president”) was probably the most influential politician of his time, extremely active and quite authoritarian. The next one (with the tittle of president) was an old royalist who like his friends was biding his time for the restoration of the monarchy, and did mostly nothing. So a clear precedent was lacking. And it’s not like there was a lot of foreign examples to look into at the time. The UK wasn’t a very useful example. The Queen’s powers weren’t real, but she was an hereditary monarch, not a democratically chosen president.

Finally, the issue was settled by a political crisis. A president who held the view that his powers were very real, but who lacked support in the parliament for many of his others political views engaged in a direct struggle with the parliament.
He utterly failed, lost popular support, and the chamber made sure he wouldn’t be involved in anything significant ever again.

Following this precedent, all following presidents kept a low profile. They were picked amongst deserving, old politicians instead of active political leaders, with the clear understanding that their main job would be, according to a French saying, the “inauguration of chrysantemiums”.
However, this result wasn’t a given from the get go. With a somewhat different chain of events, the French presidents until the late 1950 might have ended up being the real holders of power, instead of figureheads signing whatever the prime ministers handed them. This in turn might have had an influence in other European countries’ systems, since France was at the time the only European republic, hence one of the most obvious potential example of a working non-monarchic democracy.
(*) ETA : Ok, not really short :smack:

Don’t forget however that this kind of evolution didn’t take place in most European countries. Much more commonly, the monarch was ousted quite abruptly.

You are using the words in a special meaning here that you should define first. Because the Western Democracies you cite have most certainly a separation of powers into legislative, executive and judiskative. While I can’t take a vow on the system of Great Britain, I strongly suspect that no matter what system they had 200 years ago, today they also have this separation, because a country needs to meet certain requirements to become a member of the EU.

For that matter, how is the US not a parliamentary system since you have two different chambers, too: the Senate and the House?

A clear definition would certainly help answering your question.

If you mean “Do the citizens of continental Europe (GB is a bit different) prefer their current system over that of the US?” then yes, definitely, emphatically. No matter how many problems with our politicians and parties we have, the problems of the US system of two parties only are too obvious (along with minor procedural problems that blow up into big problems occasionally).

I have not heard the politicians express preference for one system over the other, only parties suggesting changes and tweaking of the existing system. Like the (current for some while) suggestion to expand popular votes (on single issues - I think California has a similar model?) from the state to the federal level, to get citizens more involved into the govt. and give them a better chance to be heard and a different venue than the normal parties and lobby groups.

Whuh? What kind of parliamentary system in what country are you talking about??? Have you never heard that in the “parliamentary systems” (whatever the OP means with that term) of Germany, France, and GB, there are loud and heated debates of different parties during the sessions?

It’s true that most western countries lack such tools of democracy like Filibustering, which is special to the US, but that’s not for lack of strife, but rather that we find it hinders discourse and finding solutions.
If you mean “in western European countries = parliamentary systems, politicians are more focused on finding a solution that on being obstructionist for the sake of winning” - in that case I’d agree with you. But I disagree that the parliamentary system is the cause of this, rather a different expectation from the public about what politicians can’t get away with, and not electing complete nutbars.

A country that is changing from one system to a different one and worries about managing the nation, the problem is not whether it’s parliamentary or not. There are a heap of factors that can topple a democracy or not. Why do the South American countries have such a long history of revolutions (aside from CIA and similar meddling there)? Partly because the population and politicians believe that the only way to get rid of the rulers is by revolt.

Wrong if we are still talking about the Western European countries the OP used as examples (I’m excepting Russia because it has a nominal system but is in reality authoritarian again). They had for centuries (not millenia) monarchs, with varying degrees (depending on which time period and which country) of parliament as advisers and councils. That’s what the Magna Charta in England was about, limiting the power of the king; and while most kings could make laws, many of them were still subject to the courts.

So actually there was a gradual development to parliament getting more and more say, until you end up with the parliamentary monarchy of modern GB or Scandinavia, where the king/ queen is mostly a figurehead.

I would really, really like to know what country and what time period you’re talking about here, because I don’t recognize it. I strongly disagree that this is in any way typical for the parliamentary system or a modern democratic, parliamentary, country.

Shortening up part of what constanze is saying, I agree with her that part of the reason so many countries have parliamentary systems is, for European countries, that they already had Parliaments way back when (we inherited the idea in part from the Roman Senate, and in part from “going to have a chat with the chief”), so the current versions are an evolution rather than something cut up from whole cloth; for our ex-colonies, that they didn’t toss out the legal systems they got from us any more than we tossed the Romans’: the Mother Country had a Parliament, the Daughter Countries got them too.

It’s parallel evolution from a single source with a dash of “checking out how the neighbors are doing it and copying those parts which seem to work well”.

One piece, certainly, is that there are sound reasons for distinguishing between the government in the American meaning and the Government in the British meaning – most notably, that voters want to be able to throw out the Government that is not sufficiently responsive to their wishes without jettisoning the whole apparatus of government and starting over again from a blank slate. So having a leader who is the head of government who is not the semi-figurehead head of state is useful – the head of state is in place to ensure continuity, while the Government can be thrown out when the voters tire of it. Another is to make the “nuclear option” dictatorial choices available for emergency but difficult to invoke. So you can cover any reasonable crisis but your present HOG cannot blow up an incident to turn it into a pretext for dictatorship,. So you vest the use of those powers in someone who cannot himself choose to use them but can exercise his good judgment whether it is the right time to let someone else use one of them. So the Head of State acts normally on the advice of the Government, but on certain rare occasions will reject that advice as inappropriate to his people’s freedom – King Haakon VII of Norway in 1940 is the perfect example of this.

As quoted by that noted Anglophile; Eamon De Valera.

I admit he has got point; when government services are going to shut down because the politicians cannot agree and refuse to do the proper thing and resign.

Absolutely. I highly recommend Iron Tears by Stanley Weintraub for anyone who wants to understand British politics during the American Revolution. George III had a lot of influence in Parliament, played favorites among MPs, and often bankrolled the campaigns of favorites, or of those seeking to unseat MPs he disliked. Lord North, the Prime Minister, definitely worked for him, and not the other way 'round. After Cornwallis surrendered at Yorktown in 1781, the King went so far as to draft a letter of abdication, so closely was the badly-failed war policy personally identified with him.

George III wouldn’t have called it meddling; he would have called it ruling. Although he did not have the power of other European monarchs at the time, he was an activist king and by far the most powerful man in the country. You can make a good case that the Declaration of Independence, in assigning responsibility to him for British acts, was speaking factually as much as symbolically. Michael Pearson’s book Those Damned Rebels, which I strongly recommend, is a good source.

The loss of royal power over the next half century was dramatic (and probably an excellent thing for Britain). After George III’s mismanagement of the American colonies, his dementia in later years, and the ineffectual regency and monarchy of George IV, the British crown was never to come back.