President Trump is sufficiently pleased with the new immigration bill sponsored by Republican Sens. Tom Cotton and David Perdue that he didn’t just endorse it but made an appearance with them to promote it. “The RAISE Act,” he said, “will reduce poverty, increase wages, and save taxpayers billions and billions of dollars.”

And the bill does contain good ideas. Regrettably, however, these are likely to be obscured by the policy that will make the biggest headlines, a 50 percent reduction in legal immigration. There is no problem at the moment with excessively high levels of legal immigration. It is not the overall number of immigrants but the composition of the whole, with too many low-skilled newcomers and too few high-skilled ones that is the problem. The bill seeks to fix that problem and should do so, which makes its effort to stanch the flow of arrivals overall both redundant and, in all likelihood, counterproductive.