This week marks the 20th anniversary since the beginning of the Iraq War - one of the most controversial conflicts in modern times.
On 20 March 2003, the US launched its first airstrikes on the Gulf state - lighting up the skies above Baghdad with an ultra-aggressive "shock and awe" strategy.
Soon after a coalition of American, British, Australian and Polish soldiers marched over the border from Kuwait to execute “Operation Iraqi Freedom”.
The US-led coalition invaded largely on the premise of alleged weapons of mass destruction (WMDs) held by Saddam Hussein’s regime, but none were found.
Revelations of faulty intelligence, and in some cases sheer dishonesty, used to justify the eight-year conflict, left many in the West very angry that their countries had been dragged into a war on dubious grounds.
Watch: Former UN weapons inspector Hans Blix says Tony Blair should face a tribunal for Iraq invasion
Of all the key actors involved in the invasion, one that often generates the most intense reaction is Tony Blair, the prime minister who backed US president George Bush and has since faced criticism and vitriol from many quarters.
Now, the former weapons inspector who was tasked with investigating Iraq's alleged possession of WMDs for the United Nations has spoken out against the former PM.
Speaking on MSNBC ahead of the anniversary, Hans Blix said that, "in principle", Blair and Bush should have faced consequences for their invasion - which is now widely regarded as illegal under international law.
He said there should be a penalty for breaking the "principle rule" of the United Nations charter - not to "use force against the territorial integrity and independence of other states".
Blix pointed to the Nuremberg Trials after World War II, and demands for Vladimir Putin to face charges following the Ukraine invasion, claiming this is very much the standard the international community should adhere to.
Asked if he thought Bush and Blair should face trial at the Hague for alleged war crimes, he said: "I think in principle, yes.
"I think they will not come, and nor will Putin come for a tribunal, but nevertheless holding a tribunal and going through the evidence will be of value.
"We hear very much from the Western world about the 'rule based international order' - well that is the one that the US, the UK and the others broke in 2003."
Blix had been asked by then-UN Secretary-General Kofi Annan to determine whether Hussein really did possess the WMDs it was claimed he was hiding.
At the start of 2003, he reported that Iraq most likely did not possess weapons of mass destruction or the means to produce them.
He asked for more time to reach a clearer verdict, but the US and UK decided they'd had enough and launched their invasion.
Blix said he felt "sadness" that he wasn't allowed more time, and said it wasn't reasonable "to close the door on inspections after three months".
He later became much more vocal in his criticism of the invasion, telling BBC Panorama in 2016 that Blair had “misrepresented the facts” when he told UK MPs about Iraq’s chemical weapon capabilities.
The Swedish diplomat said he thought Blair "had a feeling that this was an evil regime and that it was a moral thing to do away with it", but said he "did not represent the reality" when presenting his justifications.
Speaking to the Chilcot Inquiry into the UK's role in Iraq, Blix said he told Blair that while he suspected there were some "prohibited items" in Iraq, the UN's "belief in the intelligence had been weakened" by a lack of evidence.
Tony Blair and the Iraq war
One of the reasons so much anger has been directed at Blair was his apparent overstating of the danger posed by Hussein's regime to rush into a war for which the UK was poorly prepared.
For example, his headline-grabbing claim made in Parliament that Iraq had chemical and biological weapons, "which could be activated within 45 minutes", turned out to be based on bogus intelligence.
Sir John Chilcot, chairman of the Chairman UK's Iraq War inquiry, said the decision to go to war was not the "last resort" option that Blair had presented to the public.
On the eve of the invasion, Blair warned MPs about the possibility of WMDs falling into the hands of terror groups, which he said was a "real and present danger to Britain and its national security".
However, he had been warned that military action would increase the threat from Al Qaeda to the UK and open up new territory for jihadists by bringing instability to the region.
Since the end of the war, Blair has continued to attract much criticism, particularly amid ongoing political instability in Iraq, which became a breeding ground for Islamic terrorists.
Rejecting most of the criticisms in the Chilcot report, he insisted he did not mislead the country and that he "made the decision in good faith".
However, he did "express more sorrow, regret and apology than you can ever know or believe,” that the war had created chaos in the region and resulted in Iraqis becoming victims of sectarian violence.
In 2017 the High Court ruled that Blair should not face prosecution for his role in the war, but resentment still lingers among some quarters even 20 years later.
Even today, it is a lightning rod in the UK's political discourse.
On Monday, Tory MP Jacob Rees-Mogg questioned why Blair faced no charges while Boris Johnson was fined by the Met Police over "eating a slice of cake" amid the "Partygate" scandal and subsequently called before Parliament's Privileges Committee.
He told GB News: "This seems to me to be completely disproportionate when a much bigger mistake never led to equivalent parliamentary action."
Rees-Mogg added: "Harriet Harman, who now presides over the privileges committee which is looking into something completely different.
"Not a war that cost UK lives, American lives and hundreds of thousands of Iraqi lives. A war on a very large scale which was based on information that wasn’t actually factual in the end."