Text ４ 　　If one affair ends in tears, there is always a new paramour in the wings. In the 1970s the British picked up neglected US firms. In the 1980s Japanese firms paid too much for Hollywood studios and Californian skyscrapers. A decade later continental European firms rushed across the pond. By this account, Chinese firms are the latest to get the love bug, with China’ s richest man, Wang Jianlin, having paid a blockbuster $4bn to assemble a chain of mature American cinemas since 2012. 　　But this narrative is hopelessly out of date. The most accurate metaphor for foreign firms in America today is of disappointed hopes. The share of sales that European firms make in America has declined from 20% in 2003 to 17% now, according to Morgan Stanley. Foreign firms’ return on equity fell to 6%, compared with 11% in 2006. American multinationals make 12% on their home turf. 　　This broken romance reflects three deep shifts in America’ s economy. First, technology has a greater importance than it used to, and the gap between Silicon Valley’ s giants and their peers abroad has grown wider. Second, waves of mergers and acquisitions have made the economy more concentrated, which has raised the barriers to entry for outsiders. If you split the world’ s companies into 68 industries, American firms are the largest in two-thirds of them. Foreign companies in America are often subscale and too small to buy the leading firms in their sector. 　　The third reason for foreign firms’ discontent is the growth in lobbying, litigation and regulatory action in America. Foreign companies feel they are at a competitive disadvantage. 　　In the most regulated sector of all—banks—their market share has fallen to 14% from 18% in the past 24 months, partly, they argue, owing to onerous new rules. In December Barclays vowed to fight a $5bn-odd fine for mortgage mis-selling, which it argues is harsher than those faced by American banks. 　　A more populist America may require fresh tactics from foreigners. Some are working on their connections. Masayoshi Son, boss of SoftBank, pledged to invest $50bn in America after meeting Mr. Trump in December. Another option is for foreign firms to assume a more American identity, especially in some sensitive sectors where they already try to take on a local character. Rupert Murdoch shifted his media empire’ s legal residence from Australia to America in 2004. As any dating-website veteran will tell you, if you can’ t find love, change your appearance.