Shortly before he stepped down as prime minister under growing threats from the Islamic State (IS) terror group and increasing political instability, Iraq’s former prime minister Nuri Al-Maliki appointed several of his operatives to key government posts.

Among the last minute reshuffles was naming his chief of staff as the new governor of the country’s Central Bank and his secretary as the new head of the cabinet office. Al-Maliki, who had staffed government and security forces posts with cronies during his tenure, also reportedly named another partisan as the new head of the state-owned Iraqi Media Network.

Moreover, Al-Maliki, who ended his term without a budget approved by parliament for the years 2014 and 2015, allegedly left his successor, Haidar Al-Abadi, taking over the reins with empty coffers due to unchecked overspending and rampant corruption.

Though Al-Maliki was appointed vice-president in the political deal that made him step aside, he has refused to give up his prime ministerial offices in one of former Iraqi president Saddam Hussein’s former presidential palaces in Baghdad’s fortified Green Zone.

The Iraqi media has also reported that he has insisted on keeping the large army units tasked to protect the prime minister for his guard.

The message could not be clearer for Al-Abadi: Al-Maliki has been bidding to make life tough for the new prime minister by making him face enormous challenges. Yet, Al-Maliki, who reluctantly gave up his post to Al-Abadi, has not only added insult to injury as far as the new prime minister is concerned, but he has also raised tensions in Iraq’s already messy political process.

Now Al-Abadi must work with an entrenched bureaucracy in which most of those on the higher echelons are Al-Maliki loyalists and with a system created to serve the former strongman’s policies. The negative impact of Al-Maliki’s political appointees on the actions of the new prime minister and his staff is expected to be daunting.

In addition to the appointees that may get in the way of Al-Abadi, Al-Maliki has also been forcing himself into the political debate. Though his vice-presidential post is ceremonial, the former prime minister has not hesitated to intervene in controversial political issues.

He has been using his position as head of the State of Law bloc and secretary-general of Al-Abadi’s own Dawa Party to organise political meetings and discuss crucial government matters, such as its relations with the US-led international coalition to fight the Islamic State terror group.

Last week Al-Maliki told a gathering of Dawa Party supporters in Kut south of Baghdad that “all of you should stand with the government when [it moves] in the right direction and warn it against any wrong doing.” This was a veiled threat that Al-Maliki is still a heavyweight to be reckoned with and is still playing a role behind the scenes in Iraqi politics.

No one had expected Al-Maliki to disappear from public life after his forced resignation, but his comeback onto the Iraqi political scene has been surprisingly quick and aggressively bullying.

Since he came to power Al-Abadi has been subject to outbursts in social media dubbed by Iraqis as “Al-Maliki’s electronic army”. Nearly a dozen media outlets are said to be operated by Al-Maliki-hired spin doctors to spread anti-government misinformation.

Some of Al-Maliki’s cronies have been deriding Al-Abadi publicly. In an interview with the New York Times last week Hanan Al-Fatlawi, an outspoken Al-Maliki crony, described Al-Abadi as having a “weak personality” and “no courage to decide important things”.

Having promised a different governmental approach, Al-Abadi was expected to make changes to improve security and provide essential public services such as electricity, healthcare and housing.

Al-Abadi has been trying to dump Al-Maliki’s legacy by reaching out to other political forces. He has promised that his government will be all-inclusive and that his partners will share in decision-making.

Al-Abadi has also pledged to clean up the government and the security forces of corrupt and inefficient officials. One of his first steps in government was to abolish the office of the general command that was set up by Al-Maliki to run the day-to-day affairs of the security forces.

He had reportedly dismissed dozens of Al-Maliki-appointed top officers who are suspected of corruption, malpractice and incompetence. Others have been investigated, including on how they were promoted and assigned high commands despite weak performances.

On Saturday, Al-Abadi succeeded in convincing the parliament to endorse his candidates for the key posts of the defence and the interior ministers nearly one month after he formed his unity government.

The breakthrough is expected to consolidate Al-Abadi’s government as the country prepares to mount an effective military response to the IS onslaught.

Al-Maliki had previously vetoed the new Sunni Defence Minister Khalid Al-Obeid and insisted on his ally and leader of the Badr Corps Shia militia Hadi Al-Ameri for the interior minister portfolio.

There is speculation regarding Al-Maliki’s intentions in defying Al-Abadi, particularly since the new prime minister is a junior member of his own Dawa Party. There are also concerns that Al-Maliki may be trying to set up a second set of institutions or a double government, his strategy being to portray Al-Abadi as weak, ineffective and unable to face responsibility.

One theory is that Al-Maliki wants to establish himself as a Shia hero who can crack down on IS militants and other Sunni insurgent groups and ensure the future of a Shia government in Iraq.

Another theory is that Al-Maliki may be afraid that his political opponents will press the Iraqi and foreign judiciaries to bring him to account on charges such as mismanagement, negligence, corruption and even war crimes during his years in power.

Over the past eight years, Al-Maliki has been accused of power grabs and committing gross constitutional violations and overlooking or sidestepping the law. Despite damming evidence he has escaped prosecution because of the influence he has been able to exercise over the country’s judiciary.

In terms of human rights, the security forces under his command and other government agencies have been accused of all kinds of abuses and violations of freedoms, including the freedom of expression, publication, assembly and peaceful demonstration.

Under Al-Maliki’s government Iraq became a nation of corruption. Grafts, kickbacks, commissions and bribery became common practices, and while in office Al-Maliki fired three anti-corruption heads when they tried to probe his cronies.

Allegations about the corruption of his son Ahmed and other siblings abound.

Al-Maliki has also been accused of mishandling state funds, interfering in the operations of the Central Bank, and misusing assets in the Iraqi Development Fund. But perhaps the most serious charge against him is his responsibility for the disaster unfolding in Iraq today.

Al-Maliki failed to resolve the disputes with the autonomous Kurdish Region over oil-revenue sharing and disputed territories when he was in office. The Kurds finally succeeded in extracting oil themselves and selling it independently, also seizing territory as large as their original enclave.

For eight years Al-Maliki ran Iraq in a sectarian and authoritarian way which alienated the country’s minority Sunni Arabs, a policy which is primarily responsible for the unabated Sunni insurgency today.

Al-Maliki’s marginalisation and exclusion of the Sunnis and their repression by his security forces were largely responsible for the bloody insurgency and the violence that has ensued across Iraq.

Al-Maliki’s incompetence and negligence remain main factors underlying last summer’s spectacular collapse of the Iraqi security forces and the quick sweep of Sunni militants through Mosul and other Sunni-dominated provinces.

Even the country’s Shias suffered under his authoritarian rule.

In a scathing attack against him, a spokesman for the Iraqi Supreme Islamic Council Baligh Abu Galal was quoted on Sunday by Iraqi media outlets as describing Al-Maliki as an “enemy of Iraq, Islam and the Shias”.

On Monday, Shia grand ayatollah Ali Al-Sistani, who has shunned Al-Maliki for years, received Al-Abadi in an audience in a clear message of support for the latter and disdain for the former.

The quagmire in Iraq is America’s enduring folly, and the Al-Qaeda group, the forerunner to the murderous IS, also has had its own role to play in the on-going bloodbath. Iraq’s neighbours cannot be exempted either from the tragedy.

But the country’s post-Saddam leaders are primarily responsible for the catastrophe that has befallen Iraq and now threatens to obliterate it from the political map of the Middle East.

Among these leaders, Al-Maliki remains Iraq’s chief destroyer. Many Iraqis are dismayed by his legacy and are deeply concerned at the prospect that he will now continue meddling in Iraq’s chaotic politics.