Within a month, Bagdad had fallen-but an insurgency grew.

Tony Blair's decision to back the war with Iraq was probably the most controversial of his second term in office.

The UK supported the US-led invasion in March 2003 despite the failure to secure a second UN resolution authorising war.

The government argued that Iraq's refusal to cooperate with earlier UN resolutions legally justified the invasion.

The Conservatives supported the war in Parliament, but Liberal Democrats, Plaid Cymru and the SNP were opposed - and two Labour Cabinet ministers resigned.

The Iraq Survey Group could not find any WMDs

The Prime Minister told Parliament in September 2002 that Iraq possessed weapons of mass destruction (WMDs) that were an "active, growing" threat to the UK.

But after two years, no WMDs have been found.

An official inquiry dismissed the charge of deliberate deception but said some of the evidence was 'very thin'.

Mr Blair now says that overthrowing the repressive regime of Saddam Hussein and encouraging democracy justifies the war.

Conservatives criticise 'lies' on WMDs but say they still support regime change.

The new assembly met but could not initially form a government.

In January 2005 elections were held in Iraq to chose a transitional government and an assembly to draw up a constitution.

There was a substantial turnout among Shia Muslims and Kurds, but most Sunni Muslims did not vote.

The election did not put an end to the violent insurgency.

If the new government can build up its own security forces, there are hopes that UK and US troops can leave.

The Liberal Democrats would like troop withdrawals by the end of the year, while the Greens want an immediate pull-out

The police want stronger anti-terror powers.

The government warns that the UK faces a real threat from terrorists.

It wants powers to keep suspected terrorists under house arrest if there is not enough evidence to convict them in a court of law, by using control orders.

This was criticised in Parliament by the Liberal Democrats and Conservatives, who said it breached the fundamental principle of detention only after trial.

In a compromise, judges will now review the control orders, and the whole terror bill will be reviewed in a year.

Trials of ID cards have started

Labour is committed to introducing compulsory ID cards, which it says will help the fight against terrorism, crime, and illegal immigrants.

The cards would be introduced gradually from 2008 with details stored centrally.

The Conservatives support ID cards in principle, but have reservations about the scheme proposed by Labour.

The Liberal Democrats oppose ID cards because of cost and on civil liberties grounds - as do UKIP, the Greens, Plaid Cymru and the SNP.