Although many federal Liberals opt to remain aloof from provincial politics in Quebec, almost all that choose to associate themselves with any provincial party would historically pick the Quebec Liberal Party. With the Coalition Avenir Québec (CAQ) now making its debut on the provincial scene however, things appear to be changing.

And that's a problem.

The Liberal Party of Canada (LPC) -- historically at the centre of the political spectrum and nearly always in power -- is represented by a big tent of belief systems spanning from centre-left to centre-right. Debate within the party on social and fiscal issues has often been heated. Yet there has always been one issue that has brought nearly all members of the party together: national unity.

Wilfrid Laurier believed in limited government an a decentralized federation. Pierre Trudeau practiced something close to a state-run economy and fought for a Big Ottawa vision. Yet both dedicated their adult lives to keeping the country together. Those who left the party in the wake of the Meech Lake Accord's defeat brought with them the last of the fickle federalists.

Today, many federal Liberals -- understanding that the party's rebuilding process is likely going to take a considerable amount of time -- have thrown themselves into the provincial fray. Unable to secure a senior position in the Quebec Liberal Party (PLQ) establishment or feeling little previous attachment to active provincial politics, some have opted to join the CAQ.

Personal friends of mine from the federal Liberal Party have taken on important organizational roles within the CAQ. Former LPC candidates -- and at least one former Liberal MP -- have either expressed public support for the CAQ or have joined its central team. One CAQ candidate in this election was recently defeated in a race for a spot on the Liberal Party of Canada's executive team in Quebec.

I know all of these Grits to be people of tremendous integrity and I most certainly do not call their federalist credentials into question. But let's consider the facts.

François Legault -- leader of the CAQ -- is a former Parti Québécois cabinet minister, a man who has made Quebec sovereignty his life project, and a former potential PQ leadership candidate who just a few short years ago called independence an "urgent priority" for Quebec.

In order to eat into PLQ support, he stated that he would vote No if a referendum were held any time over the next 10 years -- leaving open the possibility that he would pursue sovereignty after that period of time elapses. Even if one is to believe him, that isn't exactly federalism at its best. LPC supporters of the CAQ may be helping bring to power a man who will actively pursue the breakup of the country in the not-too-distant future.

One must remember that there are in reality only two choices for the future of Quebec -- either inside Canada or outside of it. Legault defines his intermediate position as being one that does not lay the groundwork for sovereignty (allegedly) nor one that prepares Quebec to sign the Constitution of Canada.

Yet Jean Charest -- Quebec's most staunchly federalist premier in decades -- has not initiated constitutional negotiations. Being a federalist requires only support for Quebec's continued, indefinite membership in Confederation and attempts to make such an arrangement function practically.

It should be noted that a national unity crisis -- and hence a PLQ defeat in this election or the next -- would be the easiest way to rebuild the federal Liberal Party in Quebec. Indeed, Quebeckers are likely to seek clarity in the event of a referendum and would opt to vote for either the Grits or the Bloc Québécois and not for the mushy federalism of the NDP.

Yet there is something deeper at play here. In addition the problems that divided provincial loyalties would bring to an already polarized federal Liberal Party in Quebec, there remains the challenge of constructing a solid belief system for the LPC as it rebuilds. One of the principle criticisms of federal Liberals following the 2011 election was that they didn't know what they stood for.

The PLQ does in fact have a clear belief system rooted in social progress (e.g., embracing multiculturalism and going soft on language laws) and fiscal responsibility (e.g., next year's balanced budget and the pursuit of the groundbreaking Plan Nord). The CAQ doesn't -- its promises of tax cuts go right alongside spending increases in the range of billions of dollars.

But there's something even more important at play. The LPC is the only party on the federal spectrum that can unequivocally embrace national unity, Quebec nationalism and social progressiveness at the same time. The party needs to increase its cohesiveness on as many issues as possible, and hence cannot afford to succumb to a partisan divide when it comes to the one issue that has united Liberals for generations: national unity.

A non-negligible number of federal Liberals have lent their support to the CAQ. But is their support dependent upon a possible CAQ government not laying the groundwork for another sovereignty project? At least one Liberal-CAQ "dual citizen" refuses to say.

Referendum or no referendum, the Liberal Party of Canada needs strong, committed federalists advancing a clear vision for a united Canada now if it wants to successfully embark on its rebuilding voyage. Politics for politics' sake is what brought the LPC to the brink of destruction. If federal Liberals in Quebec put aside their ideals for petty politics, we'll be making the same mistake.

Follow Zach Paikin on Twitter: www.twitter.com/@zpaikin