AFAIK both [UK] and France have similar governments as the USA.

Not true at all, there are significant differences that greatly change the political climate.

In the UK, like in Canada BTW, the House of Old Farts, which is officially called the House of Lords in the UK and called the Senate in Canada, is virtually powerless. Bills get passed on to that House, but they can merely do some tiny corrections to the bill and voice an opinion about it, that the real representatives (e.g., House of Commons in UK, or Members of Parliament in Canada) are free to ignore. In other words, their role is merely ceremonial. Nothing like what the Senate is in the US (with veto power, filibusters, grossly un-proportional and un-representative of the people, etc.).

Secondly, both in Canada and UK (and I would imagine all Commonwealth nations), the executive branch is merged with the legislative branch, i.e., the executives (e.g., the minister of agriculture) is also an elected member of parliament. And, of course, the big boss (President / Prime Minister, whatever you call it) is also a member of parliament + the leader of the majority party / coalition. In other words, whatever the party wants to do (under the lead of its leader), they can do it without endless backdoor negociations and bargains at the different levels of government, as is the case in the US, which, at the very least, greatly delays everything, and at worst, locks up the entire government to the point that even a credit rating organization like Standard and Poor's has to consider de-rating the government's salvability on the explicit basis that a government completely incapable of doing anything is not going to bode well in a time of crisis.

As for France, I believe they do have a similar separation of executive / legislative / judiciary. But they don't have a Senate either. And their voting system makes more sense (multiple round system). And they do have a more healthy political landscape with multiple parties that enrich the public debates. As opposed to the US parties that spend most of their time arguing about gay marriage or abortion rights, and spend the rest of their time competing on who can best please the bankers and corporations, by cutting their taxes, subsidising them to the teeth, and undermining the livelihood of the middle class, the elderly and the poor.

Then again, our (Canadian) system has its abuses such as when the current government has the audacity to say publicly that there is really no point in debating government motions because they have a majority and will pass them regardless. And what little checks and balances as are provided by the Senate disappear when the sitting government just appoints enough senators to achieve a majority in that house.

I agree with Mike that instant run-off voting would do a lot toward making elections in this country more representative of the people's wishes. When the Prime Minister says "you won't recognize Canada once we're through with it" you just know the ride will be unpleasant. I also recall that he said that after he was elected, not while he was running.