Economic sanctions are imposed primarily as a non-violent way to press a specific government to change. But sanctions are often controversial and their effectiveness is not assured. VOA's Scott Bobb in Johannesburg takes a look at the debate over how successful sanctions have been.
Analysts say that economic sanctions, such as a ban on trade and investment, have enjoyed mixed success.
Gary Hufbauer is the author of "Economic Sanctions Reconsidered," and a senior fellow at the Peterson Institute for International Economics. He says his research shows that sanctions do have some effect.
"We would say that about a third of the cases, there has been some noticeable positive effect in achieving the result," he said. "Where are those cases concentrated? They are concentrated in what we call modest policy goals. That is, trying to shape the foreign government, the target country to, for example, free up some political prisoners, to stop the early stages of a country trying to acquire nuclear weapons..."
In South Africa for example, international sanctions are credited for helping to end apartheid and bring majority rule in 1994. Francis Kornegay is an analyst with Johannesburg's Center for Political Studies.
"South Africa's political and economic isolation, combined with the insurgency, the un-governability, definitely stretched the [apartheid] regime to the point where their calculation was that trying to hang on to the apartheid system would only bring diminishing returns and that it was best to begin to settle and go into negotiations," said Kornegay.
The director of Johannesburg's Econometrix consultancy, Azar Jammine, says that other sanctions, such as the international ban on sporting and cultural links, played a mostly psychological role in pressing for change. But he says that even these measures were not the main reason for the decision by then-President Frederick De Klerk to negotiate with the Africa National Congress.
"The overall geopolitical environment changed dramatically in 1989 and it was no coincidence that President De Klerk un-banned the ANC on the second of February 1990, precisely four months after the fall of the Berlin Wall," he said.
Jammine says communist governments provided considerable support for the ANC's liberation struggle and the demise of communism removed a major fear of apartheid leaders.
Sanctions are also said to have played a role in Libya's acceptance of responsibility for the Lockerbie bombing and its subsequent rejection of terrorism. But Libya's ambassador to the United States, Ali Aujali, says the diplomatic engagement with Libya by the international community had a far greater effect.
"Sanctions are not an instrument to change policy of other countries," said Aujali. "Sanctions affect the daily life of peoples. But what is important is how realistic we are to solve our differences. That is what solved the crisis between Libya and the West."
Analysts note that economic sanctions often hurt the powerless, the very people they are intended to help. Economist Jammine adds that sanctions, such as those against South Africa, had long-term effects that continued well after the end of apartheid.
"South Africa was largely self-sufficient, but by trying to become self-sufficient it forced the government to adopt fairly protectionist trade policies which meant erecting high tariff barriers," he said.
He says as a result high interest rates and economic inefficiencies continued for some time after sanctions were lifted and trade barriers came down.
Kornegay says another weakness is that sanctions are not always universally supported.
"There are all kinds of ways of getting around sanctions. And there was a lot of successful sanctions busting when South Africa was under sanctions," he added. "And then when you combine that with the fact that politically and in the economic interest of a number of countries they may feel an incentive to continue trading or aiding particular countries under sanctions, that compounds the challenge."
And he notes that sanctions busting was rampant in Saddam Hussein's Iraq.
Jammine at Econometrix says that in an increasingly globalized economy, governments have far less control over trade flows.
"It is becoming ever more difficult for anyone to try and impose sanctions in an environment in which the world is becoming so global," he said. "The tentacles of communications and capital flows have become so great that it's probably more and more of a challenge every day."
Although sanctions may become less effective as the global economy matures, they will continue to be used because they provide an intermediate level of international pressure lying between diplomatic communiqués and military intervention.