If you're wondering why the OECD is apocalyptic about what will happen if digital tax talks fail then look at this. 30 of the 37 OECD countries either already have in place or a plan launch a unilateral digital services tax if talks fail. https://news.bloombergtax.com/daily-tax-report-international/oecd-countries-prep-for-plan-b-in-case-digital-tax-talks-fail

Outside of the OECD, Brazil, India, Kenya, Nigeria and South Africa also have DST plans/proposals.

Even U.S. states including Washington, Maryland and New York have digital advertising taxes in the works.

The counterfactual here is that the U.S. government (under the Trump administration) argued that these taxes unfairly discriminate against U.S. tech firms and has threatened to hit any country that launches DSTs with tariffs.

If the Biden administration goes through with the threat and responds with tariffs against all of these measures, it could mean that the U.S. is ultimately embroiled in a tax and trade war with most of the OECD.