A glance at the map shows why outside powers are taking Libya's Field Marshal Khalifa Haftar seriously.
After three years of civil war, the commander's Libyan National Army holds more than two thirds of the country, and the bulk of its oil infrastructure.
That perhaps explains the smiles from France's president Emmanuel Macron on July 25 when the field marshal agreed in Paris on an embryonic Libya peace deal with Fayez Al Sarraj, head of Libya's UN-backed Government of National Accord.
Field Marshall Haftar's consent does not mean the agreement, named the Joint Declaration, will work, but his rejection would certainly have doomed it to failure.
His arrival in Paris as the person to whom negotiators had to listen represented a personal triumph for the 73-year-old commander, who has been involved in Libyan politics for four decades.
In 1969, he was one of a group of army officers who supported Muammar Qaddafi's seizure of power from former King Idris.
Qaddafi later placed him in charge of troops invading neighbouring Chad in the 1980s. When the operation was defeated by French-backed Chadian forces, Qaddafi denied the presence of troops in Chad. Field Marshal Haftar then turned against Qaddafi, later moving to the US to support opposition groups.
In 2011, he returned to Libya to command some of the forces that, backed by Nato-led air power, toppled and killed Qaddafi.
If the Libyan revolution had been followed by transition to civilian rule, the field marshal might have slipped into graceful retirement. However, militias formed during the revolution remained after the fighting ended, becoming political players in their own right. Some of these militias included militants, among them Ansar Al Sharia, which Washington has accused of killing its Libya ambassador, Chris Stevens, in Benghazi in 2012.
In February 2014, Field Marshal Haftar broadcast a televised appeal for the overthrow of the transitional parliament, the General National Congress, accusing it of corruption and failing to disband the militias.
His appeal failed to see an uprising against the transitional parliament, but it won him support among Libyans fed-up with militia anarchy.
In May 2014, the field marshal launched Operation Dignity, aimed at pushing militant groups — including Ansar Al Sharia — out of Benghazi. His growing support saw the House of Representatives parliament, which replaced the GNC in elections in June 2014, appoint him its army commander in March 2015.
In September 2016, the Libyan National Army captured four key central oil ports from a militia, the Petroleum Facilities Guard, giving the parliament control of the so-called Oil Crescent, centre of the country's production. A grateful parliament, based in the eastern town of Tobruk, then promoted Haftar to his field marshal rank.
Earlier this year, having secured most of eastern Libya, the Libyan National Army pushed west, seizing airbases in south-west and central parts of the country. On July 3, after three years of fighting, it overran the last militant enclaves in Benghazi.
The Libyan National Army's victories have come in part because it is better trained and organised than the militias, who often fight each other. It also has Libyan Air Force, whose air strikes have proved to be the trump card in recent battles.
Part of the army's success is also because of Field Marshal Haftar's blunt message.
In a country dominated by dozens of factions who make and break alliances with bewildering speed, Field Marshal Haftar has a reputation for sticking to the same uncompromising demand, which is for militias to disband. That consistency has won him supporters, who praise his commitment to bringing order to a chaotic country. It has also made him enemies among militia leaders and critics who accuse him of authoritarianism.
Following the capture of Benghazi, Field Marshal Haftar announced his intention to move on to Tripoli and rid the capital of militias, expressing the hope that this would happen peacefully with public support.
Diplomats fear such an offensive might see bloody fighting. That concern has provided impetus for a peace process begun in May when the UAE, with Egyptian support, invited Field Marshall Haftar and Mr Al Sarraj to meet in Abu Dhabi.
Those talks laid the basis for the July 25 Joint Declaration, an agreement by both Libyan leaders for a ceasefire, unity government and elections.
However, there are questions about whether Mr Al Sarraj can deliver on a key part of the agreement, which calls for Tripoli militias to dissolve.
Mr Al Sarraj's Government of National Accord was installed with UN support in Tripoli in March last year but has failed to win public backing, while also being rejected by both the parliament and Field Marshal Haftar. The Government of National Accord relies for security on the same Tripoli militias the Paris Declaration says must now dissolve, and so far none have done so.
Days after the Paris meeting Field Marshal Haftar said that "extremists" will continue to be battled by the Libyan National Army.
