ext year is the centenary of the founding of the Irish Free State and the path to full independence. It is just conceivable that Scotland could celebrate by striking out alone too. But Wales? Surely not. The Welsh Senedd elections on 6 May seem likely to confirm Labour’s Mark Drakeford in office in Cardiff. But he may have to rely on Welsh nationalist backing from Plaid Cymru. That party’s polling is following a very similar trajectory to Scotland’s nationalists a decade before gaining power in Edinburgh in 2007. After long languishing in single figures, Plaid polls steadily around 20%, running close with the Welsh Tories. At one point in 2019, YouGov briefly gave Plaid the lead. Meanwhile, Welsh enthusiasm for independence, once minimal, is running at more than a third of the electorate, or 39% “if Wales could rejoin the European Union”, according to polling. A significant 58% of the newly expanded younger vote of 16- to 34-year-olds is pro-independence in this scenario. Polls for the “non-political” YesCymru independence movement have registered an 11-point increase in support to 33% since December 2019. Whether this is attributable to Covid is moot, but the separate handling of the pandemic in Cardiff appears to have reduced previous scepticism towards devolution. Adam Price, Plaid’s leader, is a former MP and academic researcher. He knows he has a mountain to climb. Wales has independence parties like it has nonconformist chapels. The task for Price is to give independence substance, to fill what he calls a vacuum between “indy curious” into “indy plausible”. A party founded in 1925 to keep Wales Welsh-speaking must now describe how a real Wales might look after being ruled as “England and Wales” since the Tudors. Last September, Plaid published an impressive report, Towards an Independent Wales, which met the sceptics head on. It was almost a Welsh version of America’s Federalist Papers. It grappled in detail with a Welsh constitution, justice system, education, finance and foreign relations. It pointed out that there was nothing unusual in small state independence. There are seven smaller countries in the EU, and plenty such as Lithuania, Slovakia and Ireland which have complex, fiddly borders. As for relations with England, the report was openminded, examining confederal models from the EU to Benelux and Spain. It even proposed “an explanatory referendum”, in which various options are presented to the voters. Above all, the report faced head-on Wales’s dependency on British subsidy, the result of a crippling fiscal deficit of 18%. According to the Institute for Government last week, each Welsh citizen is net recipient of £4,400 a year from the UK exchequer, against England’s £90 and Scotland’s £2,500. As in Scotland, Welsh independence advocates draw heavily on Irish experience. Ireland in 1922 was as dependent financially on Britain as is Wales today. London’s postcolonial legacy to Dublin was a band of Treasury officials who made George Osborne seem profligate. At the moment of liberation, Irish pensions and welfare benefits were cut and extreme austerity imposed. Ireland entered a period of prolonged agony. Ireland was pulled round by EU membership in 1973 and by International Monetary Fund aid. More crucial was its switch from a fierce Anglophobia to a brash internationalism. The Irish government slashed taxes for immigrants and foreign companies, welcomed tourists and managed to reverse the curse of emigration. By the 1990s the Celtic Tiger was born. There was much economic strife in the aftermath of the financial crash of 2008, but I know of no Irish body of opinion that wants to rejoin England today. To those set on independence, economics is immaterial. Project fear never works. When it comes to self-determination, sovereignty is all, as the cliches of Brexit attest. Besides, no model can forecast the galvanic impact on an economy of independence itself. As the Basques said of their quasi-autonomy from Spain: “We build the road as we travel.” Wales today is better off by far than Ireland in the 1920s or 1960s, even if Plaid Cymru’s faith in national banks, commissions and enterprise agencies looks tenuous. Its chief handicap may be similar to Ireland’s 100 years ago – the potential for an excluding hostility to newcomers. Nowhere in Wales is more than an hour from England. An independent Wales is to me perfectly feasible, but it would depend not on England’s exchequer but on England’s tourists, retired people, remote workers, long-distance commuters, returning expatriates, second-homers rich and poor, anyone who can be induced to bring money and talent over the border into Britain’s loveliest country. As with the SNP, Welsh nationalism has to tear itself away from reactionary nostalgia to imitate Ireland’s hard-headed entrepreneurialism – or it will stay just a pipe-dream party. By the end of next week, the bizarre “union of four nations”, much cited during Covid, could be seriously at risk. As throughout history, England is hopeless at managing such risks. Boris Johnson seized power by championing British nationalism, yet he has only contempt for the nationalism of others. Last November Johnson called granting more power to Scotland “a disaster”, declaring devolution to be “Tony Blair’s biggest mistake”. That may soon be another quote he will deny ever having said. Simon Jenkins is a Guardian columnist