Most Democrats and some Republicans are critical of such ideas, partly because of the large (US$1 trillion or more) federal borrowing the plan would require, which might actually worsen the imbalance between revenues and expenses that Bush pointed to as a looming problem; and partly because of the problems encountered by the United Kingdom's privatized pension plan. See Social Security debate (United States). In addition, many Democrats opposed changes that they felt were turning Social Security into a welfare program that would be politically vulnerable. Portions of Bush's bill exempting private companies from social security payments have led to complaints that Bush's plan was created to benefit private companies, and that it would turn Social Security into just another insurance program.