Great news! A new age of sunshine and rainbows is about to dawn in Canada.

With a wave of his hand, Justin Trudeau will banish global warming, cancel the bombing in Iraq, shelter the Syrian refugees, order a new census, legalize pot and lift the burden of taxes from the groaning backs of the middle class.

On the second day, infrastructure dollars will wash over the land and the wicked witch will melt. We're off to see the wizard.

OK, that wizard turned out to be a huckster. And in truth, as U.S. President Barack Obama has predicted, Trudeau's pledge of "real change" probably means that his legendary hair will change. To grey. And quickly.

Just say the magic word — Senate — and see if that doesn't happen.

Honeymoons: your mileage may vary

Sadly, there's no set span for a political honeymoon. A romantic one is easy: tradition has it that you sip the marital honey until the moon's in the same phase as it was at the wedding — so, a month.

Politicians try to make it last longer. The concept was originally an American notion, beginning in the Depression with Franklin Delano Roosevelt's First 100 Days.

Judging by their poll ratings, Ronald Reagan's sunny ways gave him an eight-month honeymoon, but George W. Bush only managed three months in 2000, when half the voters thought he didn't really win.

Prime Minister Pierre Trudeau urges Canadians to cheer for U.S. President Ronald Reagan during speeches in front of the Parliament Buildings in March 1981. Reagan's honeymoon lasted eight months. (Andy Clark/Canadian Press)

John F. Kennedy did no better, thanks to the Bay of Pigs fiasco, and Bill Clinton blew his honeymoon even faster.

So what are Trudeau's chances? How can he keep the magic going and what seems likely to end it?

The easy stuff

First, there are a host of things that don't need legislation and can, indeed, be done with a wave of the hand.

Trudeau doesn't need Parliament to order the CF-18s home from the bombing mission in Iraq and Syria. Nor does he need anyone's permission to decree that the long-form census be mandatory or to set up an inquiry into missing and murdered aboriginal women.

Liberal leader Justin Trudeau criticizes Stephen Harper and Tom Mulcair for they positions on purchasing the F-35 fighter jets. 2:34

Likewise, he can name committees to study electoral reform and Senate appointments — and then blame the committees if things get bogged down.

And, of course, he can name all the women he likes to his cabinet. Plus — new ambassadors? Poof! New deputies? Zap!

New Senators? Hold it right there.

The red-faced chamber

As ghastly as Stephen Harper's experience was in the Senate, Justin Trudeau's isn't guaranteed to be much better.

For one thing, he has closed the one avenue he has to ensure that he has a majority. Otherwise, he could have just filled the 22 vacancies that Harper helpfully left unfilled with party hacks. But he can't, because he promised a bright new dawn of independent, non-partisan senators to be named by a learned committee.

Based on merit. Whoever heard of such a thing?

Prime minister-designate Justin Trudeau takes a big first step this week when he announces his cabinet. Here's a look at some elements of that decision. 1:38

Second, Trudeau has long since cast his own party's senators into outer darkness. They're no longer in his caucus. They're not Liberal senators, they're senators who just happen to be Liberals, and they can vote as they please.

But, even if they vote Liberal, there won't be enough of them. So how, exactly, will Trudeau get his legislation through Parliament with a Conservative majority in the Senate? Can he just hope that the unelected Senate will be too embarrassed to block bills passed by the elected House?

Ask yourself: has embarrassment seemed to be a problem for the Senate up to now?

OK — let's say the Senate is changed and chastened by the scandals of the Harper years. Let's say some of the new, non-partisan senators just happen to have Liberal leanings and let's say the Conservative ones don't want to invite yet more ridicule by standing in the way of a popular new government with a majority in the House.

What, then, are senators for, if not to be a check on the House? Are they more relevant if they stand up to the government or if they sit down and roll over? Remember: they can't be fired and most are eager to show they stand for something more than whining about ice-cold camembert.

But if invoking the dreaded Curse of the Senate is not enough to tarnish Trudeau's tiara, then what about that other classically Canadian curse, the one that's wrecked so many new dawns before?

Of course. Federal-provincial relations.

Bring on the premiers

Is there a more eye-glazing topic in Canadian politics? Nobody wants to hear about it. Stephen Harper avoided premiers conferences like the plague because he knew that a talk-fest with the premiers would drive millions of Canadians to lunge for the off button.

Trudeau is greeted by Ontario Premier Kathleen Wynne at Queen's Park in Toronto on Oct. 27. (Chris Young/Canadian Press)

And what does much of Trudeau's new dawn depend on? Ah, yes: federal-provincial relations. Please don't doze off as we recite the list. Ready?

Climate change. Trudeau's inviting the premiers to Paris for the big climate summit at the end of the month. Don't expect them to sort it all out on the plane. We've got a crazy quilt of provincial ideas — cap and trade, carbon taxes, indifference. Trudeau hopes he can herd all these different cats into one federal commitment to do something, somehow.

Of course, the Conservatives already did that — pledging to cut emissions 30 per cent by 2030.

But how were we supposed to get there? Nobody knew. Does anyone know how the Liberals will do better? Nope.

Next: infrastructure. We all love infrastructure. But which sort, exactly? That depends on the provinces and the municipalities who propose projects and hope the feds will pay. The Liberals say they will spend an extra $5 billion on infrastructure in their first year, split between transit, "green" projects (whatever they are) and "social infrastructure" (whatever that is).

Perhaps it means that infrastructure dollars will be redirected from Conservative ridings to Liberal ones. But perish the thought. That would never happen, right?

Trudeau also pledges to negotiate with the provinces on employment insurance, a new health accord, child care, job training, an "energy strategy" and agriculture. So that should make enough federal-provincial conferences for a full four-year mandate.

How long before Canadians get nostalgic for the not-so-sunny ways of Harper, who decided in 2011 what he wanted to pay for health care and then just told the premiers that's what they were getting. You've got to admit, it was efficient.

Of course, NDP Leader Tom Mulcair railed about it constantly, calling it a "$36-billion cut" to health care. And voters shared his outrage at this affront to the provinces so much that they bounced Mulcair out of the Opposition leader's chair.

Careful with the hair

So will it be the Senate or the provinces that put sand in Trudeau's gears? Will there be, instead, some self-inflicted pratfall or some external calamity?

A political honeymoon can be wrecked all too easily — even by a haircut. (Chris Wattie/Reuters)

In the immortal words of Donald Rumsfeld, stuff happens. A honeymoon can be wrecked all too easily — even by something Trudeau has in abundance: hair.

Remember that time in '93 when a newly elected Bill Clinton held up air traffic in Los Angeles so he could have a high-priced haircut on Air Force One?

Oh, sure, the story eventually turned out to be bogus. No flights were delayed. But it was too late. Clinton's honeymoon lay in ruins. Nice hair, though.