Announcing its intention to pull out of the Northern Ireland Executive, the Ulster Unionist Party blamed alleged continued links between Sinn Féin and the Provisional IRA for leaving them with no choice.

Despite these circumstances being so serious and damaging to the Executive’s credibility, however, the UUP may have played its “get out” card too late.

Even if the Democratic Unionist Party follows suit and our governing institutions fall, Sinn Féin as an electoral force is not going away.

Whether or not this is an act of political opportunism on UUP leader Mike Nesbitt’s behalf, it has nonetheless placed the future of power-sharing in the hands of Peter Robinson’s DUP.

Nesbitt has jumped and has challenged Robinson to follow, but the DUP can yet call Nesbitt’s bluff.

Nesbitt’s decision comes in light of serious questions surrounding law and order, but why did he not pull the plug sooner?

Jumping with a disgruntled SDLP at that time of Sinn Féin’s welfare reform u-turn would have been logical; we could have had a principled, coherent non-mandatory coalition-ready opposition.

Instead, Nesbitt jumped following police claims made without full evidence disclosed; a move which seems premature.

With the SDLP set to stay within the Executive, the UUP are on their own.

The DUP must decide whether to be led by Nesbitt in collapsing the Assembly, or to stay and let the PSNI investigation and questioning of Sinn Féin continue.

Staying requires taking flak in the short term; but in the long term the crisis might subside, Stormont may survive and Sinn Féin will come under increasing pressure on both sides of the Irish border.

What’s more, with the UUP cast to the opposition benches on its own accord, Robinson’s party will become more dominant than ever at the Executive table.

The DUP will have effectively swallowed up its nearest realistic rival in government by taking its fifth ministerial department.

The DUP can decide to save face, to give up on Sinn Féin completely and Stormont prematurely, effectively handing over decision-making powers to Westminster.

On the other hand, it might tighten its grip by biding time, keeping the faith whilst marginalising the UUP to the point of complete irrelevance.

It’s decision time for Peter Robinson: to play it safe and as First Minister give up on devolution; or call Nesbitt’s bluff and risk it all for one last go at monopolising the unionist vote.