OTTAWA - Every campaign war room has pails of political dirt held at the ready until it can be thrown for maximum muddy impact into the faces of reeling opponents.

The unofficial Liberal rule is that there's no statute of limitations on dredging up attack material from the ancient history of first-time leaders in a national campaign.

The theory is that it's fair game to use the archives to malign newbies without a leadership track record to provide an unfriendly introduction to the voters.

That's why Andrew Scheer's personal record of awkward statements and outdated views were considered fair game and unleashed recently as low-calibre ammunition in a pre-emptive strike by the Liberals.

And it worked like a charm. Scheer disappeared from media view for almost a week after a 2005 video featuring his gay-marriage opposition was put on social media by Public Safety Minister Ralph Goodale.

A week later, it was a clip of Scheer's since-cancelled funding plan to help faith-based private schools and homeschooling posted by the Economic Development Minister Navdeep Bains.

And if this is rolling out before the election is even called, well, that can only mean the worst is yet to come.

A problem confronting Scheer is that his personal beliefs have likely not fundamentally changed over the years. They're merely politically inconvenient now and therefore to be glossed over with repudiations which lack conviction and clarity.

The other reason Scheer is being targeted so personally is that this election is increasingly likely to be a Trudeau-erendum on the prime minister's performance.

That forces the Liberals to demonize their key opponent, who only boasts an uneventful record as a House of Commons Speaker, as a social conservative wolf loosely disguised as a politically-correct sheep.

They have some fire to back their smoke. After all, it was a push by the social conservatives who handed Scheer the Conservative leadership and they obviously expected something for their support.

So, as unfair as it is to splice regurgitated history into a changing current reality, it's understandable why the Liberal's personal beat against Scheer will go on as the campaign begins and gets even nastier.

Of course, there are no better angels here. Any onslaught of negative ads against Scheer will be matched with plenty of gross exaggerations and twisted embellishments of the Justin Trudeau record from the Conservative side.

So brace yourself Canada.

If, as usual, truth is the first casualty in any war of words, this campaign is going to be a factual bloodbath.

That's the Last Word.