A new study of defense department spending previewed exclusively to the Guardian shows that most of the Pentagon’s discretionary spending from 2020-2024 has gone to outside military contractors, providing a $2.4tn boon in public funds to private firms in what was described as a “continuing and massive transfer of wealth from taxpayers to fund war and weapons manufacturing”.

The report from the Quincy Institute for Responsible Statecraft and Costs of War program at Brown University said that the Trump administration’s new Pentagon budget will push annual US military spending past the $1tn mark.

That will deliver a projected windfall of more than half a trillion dollars that will be shared among top arms firms like Lockheed Martin and Raytheon as well as a growing military tech sector with close allies in the administration like Vice-President JD Vance, the report said.