The exploratory talks between Fianna Fáil and Fine Gael about forming a government will be underpinned by a key political strategy on the part of the two parties. It is the portrayal, to party supporters and the public, of Sinn Féin as a sinister force in Irish politics and unfit for government.

This strategy will be aimed at preparing the way for a government involving the two parties.

The Fianna Fáil leader Micheál Martin is a key student of history, and his attack on Sinn Féin in the Dáil last week was no doubt based in part on that. Fianna Fáil, as he sees it, is the republican party, and not Sinn Féin, overseen by the IRA army council and ambivalent about the IRA’s paramilitary past.

While some of his Dáil colleagues might have had reservations about its severity, many of the party’s grassroots were delighted by Martin’s robust performance in the aftermath of a disappointing election.

Ideology aside, the timing and vitriolic nature of his speech had a strong political dimension at a time of stalemate in the aftermath of an inconclusive general election. It had all the hallmarks of making Sinn Féin the bogey party in the formation of the next government, with the imperative of keeping it out of power at all costs.

This should pave the way for public acceptance, and, more crucially, acceptance by the Fianna Fáil grassroots, of an alliance with Fine Gael and others, something Martin’s party dismissed with contempt in 2016.

Sinn Féin received a significant mandate from the electorate and there is now a cross-party consensus that voters are looking for change. When the Dáil met last week, Sinn Féin president Mary Lou McDonald secured the psychological victory of getting most votes to be taoiseach. But the party is nowhere near securing enough votes to form a government.

In the numbers game, a Fianna F\áil/Fine G\ael/Green coalition now seems the most likely, given that the Social Democrats have ruled out involvement in such an alliance.

Selling that to the Fianna Fáil and Fine Gael grassroots might not be that easy, given the long history of bitterness between the two parties, born out of the Civil War. But it could be made easier by portraying Sinn Féin as a dangerous party that must be kept out of government.

Delegates at the Fianna Fáil and Fine Gael national conferences, ratifying a programme for government, would be voting for a coalition involving the two parties in the “national interest” as much as anything else. The change demanded by voters could be provided in radical policy documents, particularly on housing and health.

Interestingly, following Martin’s Dáil attack on Sinn Féin, Taoiseach and Fine Gael leader Leo Varadkar weighed in on social media with a strong attack on president McDonald. Although there are reservations among some in Fine Gael about going into power, its attractions are likely to be too great to resist.

Fianna Fáil and Fine Gael seem destined for government, with Sinn Féin their common enemy. It is as much a political strategy as an ideological battle.