Just talking here without relevant detailed facts... Just an off-the-cuff opinion.
The USA funds about 25-30% of the UN and only manages to retain a permanent seat on the UN Security Council, with no other benefits to the USA. The USA provides most of the funding and support to NATO, with very little benefit in return. ........There are 193 countries in the UN. It’s ridiculous for the USA to be paying so much more to the UN than the other members! Make the UN move out of the USA!
Great Britain is spending tons of money to support the EU and the EU does little or nothing to support GB, but it increasingly asks for more liberal changes and money.
Brexit would permit GB to spend more in repairing their failing economy and society, as well as rebuilding their military forces. ...........Would be tough to do, since it seems the Parliament there has been taken over by extreme liberals who enjoy giving council housing to Islamic terrorists who rape their children.
The UN does give the US some benefits due to the veto rights, but yes, the % paid in is a relic of the 1970s and 80s and should be changed and based on either GDP or GNI/cap
About NATO — this is a cover for the US to have an “alliance”, that’s the benefit. However this should again be changed for the other countries to pull their weight and spend 2% of their budget on defence
"what good have the Romans ever done for us" -- ok, jokes aside, read my posts above about the UK getting entry to a vast market which they wouldn't get otherwise and also being part of a strong negotiating block to negotiate with the US, CHina, INdia etc.
Many Eurosceptics rage against the UK’s annual £18bn transfer to the EU. Nigel Farage, leader of the pro-Brexit UK Independence party, has claimed that being in the bloc costs Britain £55m a day — which adds up to more than £20bn a year.
But the UK’s net transfer to the EU falls far short of such claims. A rebate secured by Margaret Thatcher in 1984 emphatically reduced the bill from the headline figure. London sent £13bn to Brussels last year. Against that, the UK received £4.5bn from the EU in regional aid and agricultural subsidies, and the private sector received a further £1.4bn direct from the EU budget. That takes the net cost of membership to about £7bn, less than half a per cent of national income — about £260 a year for each British household.