Many constituents have contacted me to ask my position on the government proposal for air strikes against Isil targets in Syria. I wanted to lay out my thinking at this point ahead of the parliamentary debate and vote.

A number of colleagues who’ve been MPs for many years have told me that this is the most difficult decision they’ve ever faced. It is a fine judgement call, and it’s not one I’m going to make lightly. I will continue to look with an open mind at the case presented by the government and at other evidence; consider the advice of experts on the issue (including Syrian people); and consider the many representations I am receiving from constituents and others. There are further briefings and discussions taking place over the next two days before the debate itself.

Authorising military action is the most serious decision an MP can make and deserves to be treated as such. Those who characterise it as a purely political Tory v Labour issue are being unhelpful. The socialist president of France has asked the UK government to join action. There will be Conservative MPs who will vote against. This is more important than party politics.

Similarly, those who are trying to reduce it to a question of support for the Labour leadership are wrong to do so. If I vote against, it won’t be because of support for Jeremy Corbyn, just as if I voted in favour it wouldn’t be because of support for David Cameron. This is a decision that MPs will have to live with for the rest of our lives. I will make my decision because I think it’s the right thing to do.

Neither does either side of the argument have a monopoly on principle. I have decent, thoughtful colleagues who will be voting for and who will be voting against increased military action – in either case it’s because they think it’s the best way to help save lives and end conflict in the long term. Both decisions deserve to be respected because I know they will not be made lightly.

Isil are a group of fascists who have committed mass murder in recent weeks in Tunisia, Ankara, Paris, Sinai and Beirut. They have been behind seven thwarted attacks in the UK, and they will undoubtedly try to strike here again. They target Muslim people as viciously as non Muslims. The question is not whether their poisonous ideology and murderous activities should be stopped, but how.

It’s generally agreed that there needs to be an approach which includes diplomatic, political, and economic as well as military action. We also need a comprehensive humanitarian plan to deal with the Syrian refugee crisis, as well as a thorough reconstruction plan.

For those who say we shouldn’t get dragged into military action, it needs to be pointed out that we are already involved – carrying out air strikes against Isil targets in Iraq. They have made a difference to the campaign against Isil, and minimised civilian casualties. The government are now proposing we extend air strikes to Isil targets in North Eastern Syria. The  language of people who refer in very general terms to “the bombing of Syria” is very unhelpful. No one is proposing indiscriminate bombing of Damascus. There are specific Isil military and economic activities around Raqqah which are proposed to be targeted. There is a logic to extending the strikes against Isil which are currently taking place in Iraq to the same targets across a border which Isil do not recognise and does not effectively exist.

I am not opposed to military action in principle. I agree that a strong moral and legal case for action has been made. United Nations Security Council resolution 2249 calls on all member states to take “all necessary measures” to tackle the “unprecedented” threat of Isil.   But the key question now is whether the government’s plan for action in Syria is likely to work, and to do more good than harm. That is where I have concerns.

Based on briefings we’ve received, I believe that UK aircraft would add to the coalition strike capability. But it’s clear that this will not defeat Isil without a wider military strategy, including ground troops. David Cameron has rightly ruled out the possibility of UK troops on the ground. The government has said there are 70,000 Sunni fighters who can make up a ground force. This seems to me a very unconvincing claim. These fighters are in a large number of disparate groups many of whom are focused on fighting the Assad regime. They do not look like a coherent potential ground force. And without a wider military strategy that includes ground troops, air strikes in isolation will not defeat Isil. It may be a gesture of support and solidarity with our allies that brings its own dangers.

In my view there is a real risk of Isil using an escalation of military activity to boost their (effective) propaganda war. In 2003 I argued that action in Iraq would lead to increased radicalisation. Unfortunately I was correct. While this is a quite different situation to 2003 Iraq, it’s important to learn the lessons of past mistakes. My worry is that Isil will exploit escalated action to further add to their narrative of a growing world war between the west and Islam. This is a particular concern if an attack goes wrong and there are significant civilian casualties. This danger of increased radicalisation, and playing into Isil hands, is one that needs to be taken seriously into account.

The political and diplomatic strategy also needs further development. The chaos that Bashar Al-Assad has reaped in Syria has been a key factor in driving people into the arms of Isil. There are Syrian people whose judgement I trust who tell me that we can’t defeat Isil without removing Assad. The way to remove him is not through military action; there needs to be a negotiated transition plan to a post Assad Syria. While I welcome the progress at the discussions in Vienna, I’m not convinced the plan is yet sufficiently advanced. Until we have a coherent plan that will lead to a ceasefire in the civil war, moderate Sunnis who are fighting the regime will surely not be part of the ground force that is necessary to defeat Isil. And without a coordinated ground force, air strikes alone run the risk of being counter productive.

These are complex issues that MPs have to take into account in making a judgement. There is no easy answer. In making a decision, I will continue to consider representations and evidence, and will wait to see the wording of any proposed motion. But while I am not against further military action in principle, I am yet to be convinced that the case for this action is made.