In the EA movement, there's a lot of enthusiasm for significantly increasing the number of immigrants able to come to countries like the United States each year. This would help the global poor in two ways: it would directly help immigrants who come to rich countries but wouldn't have been able to without the policy changes, and it would help family members of those immigrants who remain in the home country but receive remittances.
But lately, I've been thinking a lot about other policy changes on the part of rich countries that could greatly benefit poor countries, ones that don't get discussed as much in the EA movement. Some ideas:
Increasing government aid to poor countries: This is kind of obvious, and I suspect many people dismiss it on the grounds that most voters wouldn't support it. But the President's Emergency Plan for AIDS Relief under George W. Bush suggests that efforts in this area may be more feasible than commonly assumed.
Debt cancellation/creating a global bankruptcy process: It might be tempting to assume that it would be easier to get money for, say, programs to combat disease than it would be to get money for outright cancellation of the debts of poor countries. On the other hand, the fact that many poor countries have debts that were originally contracted by corrupt dictators creates a moral case for debt cancellation that many find compelling.
There's also the argument that creating a formal system for countries to go bankrupt would be an important reform, because well-designed financial systems need a bankruptcy process. This is especially true when we're talking about government debts of countries that borrow in foreign currencies, who can't simply reduce their debt burden thought inflation (something the United States could do if it really had to). The idea of creating an international government bankruptcy process has advocates from Nobel Prize-winning economist Joseph Stiglitz to Pope Francis.
Abolishing rich-country agricultural subsidies:
Like tight restrictions on immigration, there's a strong economic case to be made that agricultural subsidies don't actually help rich countries. But they do potentially do great harm to farmers in poor countries. I'm not very confident about how large the harm is–I've heard claims that agricultural subsidies cost farmers in developing countries $24 billion per year
, though I haven't tried to check that particular number.
Of course, any of these policy changes would be more difficult to get implemented than simply donating a little more to AMF or GiveDirectly, so the potential benefits would have to be weighed against the difficulty of bringing about these policy changes. Still, they look worth investigating. I've only started looking into them myself, which is why I'm creating this thread, so that if anyone has anything to add to what I've said, or has other ideas for things that could be high-impact, they can post their ideas here.