What happens when two southern Africa giants pit themselves against each other? Robert Mugabe and Graça Machel couldn’t seem like more polar opposites if they tried. And their recent comments on migration in the region reinforce their differences.On the side we have Mugabe, who has led Zimbabwe since the country gained independence from Britain in 1980, first as prime minister and then as president since 1987. A hero in the minds of many Africans, especially in the 1970s, Mugabe has presided over the most spectacular fall from grace. The country once known as the bread basket of Africa has, since 2000, seen its GDP decline by roughly 40%, in part due to his land reform programme and hyperinflation. And millions of Zimbabweans have fled the economic crisis and political violence.Machel is a renowned international advocate for women and children’s rights and has been a social and political activist for many decades. She is the widow of Nelson Mandela and former Mozambique president Samora Machel and has been outspoken on the xenophobic violence that has ravaged South Africa. At the memorial of Mozambican Emmanuel Sithole, killed during such an attack, she made an impassioned plea to Africans to stop the violence and referred to herself as the most visible face of a foreigner in South Africa. This week, Machel also urged the Southern African Development Community region to relax border controls imposed on them by colonialism. This was in contrast to a speech made by Mugabe following a recent SADC summit in Harare. He called on African nations to stop their citizens from migrating – which seems ludicrous since an estimated one million Zimbabweans live in South Africa.According to Mugabe, people shouldn’t want to leave their home countries. He suggested that countries should fix their problems in order to retain their citizens: “So people should get back to their own countries. It’s not just one [problem] for South Africa to resolve but for us, we the neighbouring countries, to resolve. Our people should not have the instinct of rushing into South Africa.”It’s a charming ideal, assuming that all countries are able to offer their citizens opportunities. But people have been migrating since the beginning of humankind, following the seasons and making their way to fertile land. People still follow the opportunities – economic prospects, better education systems for their children – or leave the threats – crime, being slaughtered because of who they are, hunger or poverty.Machel hit the nail on the head when she said: “I am South African. I am Mozambican; I am Malawian; I am Swati … I belong to any of the nations especially in southern Africa,” she said. Long before the colonial borders were imposed, the San people populated southern Africa for about 22 000 years. Then, sometime between the second and fifth centuries, Bantu people from western Africa crossed the Limpopo River. By the time the sixth century rolled on by, the Eastern Cape was inhabited by the Swazi, Xhosa and Zulus. The Dutch arrived in the Western Cape in the 1600s, followed by Indian slaves from the colonies, and then, in the 1800s, the English. The Dutch started migrating northwards.Also, in the early 1800s, the event known as the Mfecane occurred, a period of widespread chaos and warfare. By the 1820s, 2.5 million starving, homeless people roamed southern Africa looking for reprieve.Not much has changed. People continue to migrate. So who does imposing borders on people and restricting movement really serve?The first true passport is commonly credited to King Henry V of England – no real surprise there – circa 1414, as a means of helping his subjects prove who they were when they were in other countries. But paperwork requesting safe passage has been traced as far back to 450BC, in the Hebrew Bible (Nehemiah 2:7-9), when Nehemiah, an official serving the Persian king, was given a letter requesting safe passage for him en route to Judea.What would a world with no borders, no restriction on travel, look like? Would it eliminate poverty? Some economists think so, and have been making suggestions on the topic since at least the 18th century.Michael Clemens, is a senior fellow and research manager at the Centre for Global Development where he leads the migration and development initiative. He has campaigned for a “modest relaxation of borders” for years. In a piece in the Guardian, he wrote that easier “human mobility between countries would bring more global economic prosperity than the total elimination of all remaining policy barriers to goods trade – every tariff, every quota – plus the elimination of every last restriction on the free movement of capital.”People have no control over where they are born, or the circumstances in which they are born. The person most affected by restriction of movement is the disadvantaged one. The anti-immigrant violence that has ravaged South Africa is one example of this. As Mugabe pointed out, the immigrants “are people who voluntarily go to South Africa. They think South Africa is the heaven, our heaven in southern Africa”.Leaving one’s home and moving thousands of kilometres is no easy task. It’s not for the weak. It’s for people who have no choice but to make a life for themselves, to make money. And many of the immigrants to South Africa have done just that, thriving on the back of hard work and dedication. Many of the richest people in South Africa are products of that. Ivan Glasenberg, worth about R61.48 billion, holds South African-Australian-Israeli triple citizen. His father was from Lithuania. The Oppenheimer multi-billionaires descended from an assimilated Jewish family of German origins. Many more examples can be found without looking too hard or reading too much. There are those people who fear that even a minor increase in migration will wreck their own economies and societies. We’ve seen this mindset here. Yet those fears are the same kind that gripped the United States many years ago. The nation that was built on immigrants is now the richest country in the world.