Could Britain have built the G3 battlecruisers?

Could Britain actually have built the G3s if the Washington treaty negotiations failed?

Yes. Britain could redirect some debt-repayment expenditure and draw on the extensive shipbuilding capacity still available in the early 1920s.

Britain's war debt did not by itself make four G3s unaffordable. The government prioritised repayment, and could instead have repaid more slowly while spending more on construction. In the early 1920s, extensive shipbuilding infrastructure remained available and competition for work could reduce prices. By the 1930s, new orders also had to pay for rebuilding capacity lost during the construction pause. The broader argument traces Britain's later financial difficulties through several successive shocks and policy choices, including the end of Lend-Lease, instead of assigning the entire decline to World War I.