One of the murkiest intelligence tasks in the war on terror is trying to locate, and neutralize, sources of money for the Islamic terrorists. While the Taliban has lots of income sources (heroin production and smuggling, kidnapping, extortion of local businesses), al Qaeda is more dependent on contributions, often from donors far away (in the Persian Gulf, Europe or North America.) Al Qaeda has lots of competition for that money. Hamas and Hezbollah are popular recipients, and its considered bad form to criticize competitors for precious terrorist charity dollars. Al Qaeda has another problem, in that have a well earned reputation of being infiltrated. That puts donors at risk from local police. It wasnt always that way. Before 2003, the Arab governments generally looked the other way when wealthy locals donated money to Islamic charities that were known to be fronts for terror groups. But in 2003, al Qaeda broke the unofficial (but very real) truce with their Arab host countries, by carrying out attacks on Saudi oil facilities. That was a big mistake, because even religiously conservative Arabs understood that without the oil wealth, there would be no there there in Saudi Arabia (and most of the rest of Arabia.)
Al Qaeda has to move large amounts of cash out of the Persian Gulf, because many of the traditional methods (like the Halwa system and commercial banks) were under heavy attack by Western counter-terror organizations. The money was hard enough to obtain, without using while getting it to the terrorists who needed it. When Iraq was the main battlefield, it was much easier to deliver the money. But now the destinations are Afghanistan, Pakistan and points east. And the counter-terror operatives are waiting, and watching, and ready to pounce. Seizures of money is often deliberately kept out of the news, because its been learned that sometimes the trusted courier cant be, and disappears with the cash. Al Qaeda can never be sure if the courier was a thief, or a victim of good intelligence.
Al Qaeda has a hard time getting new, and safer, collection and movement methods out to the fund raisers and couriers. The new methods must be posted on web sites. These are hidden, sort of, but not from the counter-terror operatives. Another problem is that the Taliban, who dont get on well with al Qaeda, have a lot more cash. But its so humiliating for the Arab dominated al Qaeda to beg the Taliban for cash. The Arabs consider themselves superior to the Afghan tribals, and the Afghans have grown to greatly dislike Arabs because of this.
The battle against al Qaedas bank account has been a success. Over the last few years, those who monitor pro-terrorist web sites, have seen more pleas from al Qaeda groups for cash to keep the killing going. But the cash isn't arriving nearly as frequently as it used it, and that has played a major role in reducing the number of major terror attacks in many parts of the world.