As a progressive Labour MP I believe we have to choose and shape Britain's future place in Europe and in the world. As the global village becomes smaller and more connected, we know we must build a world where power, wealth and opportunity is in the hands of the many, not the few.
In September, as Labour's shadow international development secretary I visited Lebanon, a country on the front line of the refugee crisis.
I saw the work of Islamic Relief and other charities and humanitarians, working to help the estimated 1.5million Syrian refugees who have sought sanctuary in that country. One in four people in Lebanon is displaced from Syria.
I met Syrians fleeing both the brutality of Assad's regime which has killed 95% of the civilian casualties in Syria. And I met refugees fleeing the thuggish theocracy and terror of Daesh.
Iman, a 65-year-old grandmother from Aleppo, was imprisoned by Assad for two weeks. She had bravely returned to Syria after her son was killed, to rescue her five orphaned grandchildren. They now live in a shack made of breeze blocks, cardboard and plastic sheeting on a hillside outside Sidon.
Hadia told me how her husband, a Red Cross volunteer, was killed in Syria. Her four older children are still trapped in Homs. Ahmed from Raqqa, and Yousif from Mosul in Iraq, fled their homes with their families when DAESH took over their cities.
The humanitarian crisis in Syria is massive. Over 250,000 Syrians have been killed, and more than 4.7million refugees have fled. Six million people have been internally displaced, having suffered attacks from cluster munitions and chemical weapons, and the collective punishment of siege warfare. 60,000 people have disappeared and their desperate families pay extortionate sums of money for news of their loved ones or just to receive their body for burial.
Assad's reign of terror has destroyed his country's economy - it is now a war economy based on looting, corruption, arms and people smuggling. Thousands of civilians live under siege, their access to basic services denied, their condition simply unknown.
In August 2013 this House voted against the government motion to back military action in Syria. The vote was prompted by a sarin gas attack on civilians in eastern Damascus, which killed 1,400 people, 426 of whom were children.
The UN doctrine of the responsibility to protect (RTP), allows military intervention to protect civilians from genocide and war crimes by their state, and provided a valid legal basis for intervention. Using Chemical weapons on sleeping civilians is a war crime.
With the albatross of Iraq hanging around both parties' necks, it was an understandable but unforgivable mistake and the one vote that I shall regret forever.
That vote weakened the Obama government's resolve, and the movement to intervene in Syria melted away. The West effectively told Bashar Al-Assad that he could do what he liked to his country's people and that we would not act, no matter how terrible his crimes.
The war in Syria had at that point claimed 100,000 lives and led to two million people fleeing their homes. We will never know the cost of the action that we did not take. We can only count the terrible cost of our inaction.
The result? A Daesh-run caliphate. The refugee crisis, and a war without law and without end in Syria.
Syria's ungoverned space allowed Daesh to move in, expand to Iraq, recruiting 30,000 fighters from over 100 countries around the world. And the West's failure to protect the Syrian people from Assad's state terror opened the door to Daesh's caliphate and their offering of resistance to his regime.
The extremists have benefitted from chaos in Syria and that chaos has spread to Iraq. Daesh has gained ground, money, weapons and fighters. It has used the internet to recruit alienated Westerners to its nihilistic death cult. It also controls an area the size of Great Britain with a population of 6 million people. It captured Ramadi in May, 70 miles west of Baghdad and Palmyra, east of Damascus in June. This progress has occurred despite UK involvement in airstrikes in Iraq and US backed airstrikes in Syria.
In September 2014, at the request of the Iraqi government, our Parliament voted to engage in airstrikes against Daesh in Iraq. Daesh had entered Western Iraq from Eastern Syria. Coalition forces have helped local troops retake one third of the territory lost to Daesh. RAF planes are attacking Daesh fighters in Iraq but turning back at the border with Syria, a border which is meaningless to Daesh. This weakens our fight against Daesh's terrorism.
A Daesh extremist murdered thirty British holidaymakers in Tunisia in June. We know that our security services have already thwarted seven planned attacks on British soil. The horrific attacks in Paris have highlighted the need for the UK to combat Daesh in Syria. We cannot continue to outsource the difficult bits of our foreign policy to the USA and France.
Some have blamed the attacks in Paris on Western intervention in the Middle East. Stop the War claiming that Paris was 'reaping the whirlwind' of intervention is woolly thinking, reflexive anti-Americanism. The Paris terror attacks were not an attack on Parisians; it was an attack on the freedoms we enjoy in the West. An attack on our way of life.
Russia has now forced our hand by launching airstrikes and President Hollande, from my sister socialist party, is appealing for the UK to help tackle the terrorists.
The choices are difficult. Our inaction in 2013 has left us with no easy choices in Syria. Airstrikes must be part of a comprehensive diplomatic, humanitarian and political peace strategy for the Middle East, in particular the rebuilding of the Syrian state.
But there is no hope of negotiating with Isil. We must stop the flow of fighters, finance and arms to their HQ in Raqqa.
For my party there will be choices too. Choices around how to apply progressive values in a changing, challenging world. Hard choices in which we must learn the lesson that failure to act carries consequences every bit as grave as the consequences of action.
Daesh is a fascist organisation that must be defeated. The longer we leave it the harder it will be. I will be voting in favour of air strikes this evening.
Mary Creagh is the Labour MP for Wakefield and a former shadow secretary of state for international developmentSuggest a correction