对这件事情有点兴趣爬文然后搜寻了一下。
https://www.theguardian.com/world/2022/feb/11/biden-7bn-frozen-afghan-
reserves-taliban
The money – which includes currency, bonds and gold – mostly comes from
foreign exchange funds that accumulated over the past two decades when
western aid flowed into Afghanistan. But it also includes the savings of
ordinary Afghans,
被冻结的资产，主要来自于外汇基金，在这二十年西方援助环境中，积累起来。
但也包括了普通人的存款。
https://www.dailysabah.com/business/finance/low-on-dollars-afghan-currency-
reserves-mostly-inaccessible-to-taliban
Central banks, especially in developing nations, often park their assets
overseas with institutions such as the Federal Reserve Bank of New York
(FRBNY) or the Bank of England (BoE).
“As per international standards, most assets are held in safe, liquid assets
such as Treasuries and gold,” Ahmady said on Twitter, confirming assets were
all held at the Fed, BIS, through the World Bank program or other bank
accounts.
开发中国家，以及此例中的阿富汗，把大部分资产放在海外，以流动性资产的方式存放。
https://tolonews.com/business/central-bank-reports-increase-foreign-
exchange-reserves
In 2018, Afghanistan’s revenues from currency exchange reached $100 million
which has been unprecedented in the recent years, the Central Bank governor
Khalil Sediq said.
He also proposed that the money should be invested in the creation of an
agricultural loan bank or in something else that can bring more money to the
country’s treasury.
2018靠外汇换汇赚很大，并且更强调投资循环生财。
In Afghanistan, however, still, around 50 percent of the development budget
comes from foreign support.
尽管有50%的发展预算仍来自国外援助。
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不算专业的拼凑理解是:
这无关于贸易顺差，而是一个技能树有点歪，
在顺境下投资颇成功，但又把主体资产放在海外的银行。
(那些钱的来源跟西方援助有间接关系，但却又不是直接把帐混在一起)
所以其实冻结本身银行没有说什么，可能还庆幸钱没落在塔利班手里，
但说要分钱给美国911受害者他们就抗议了，强调钱是人民的而且来路正当。