This week, the Trump White House and Republican-led Congress plan to dust themselves off from a bruising self-defeat on a GOP health-care bill and begin work on reforming the tax code, something that hasn't been done in some 30 years. The failure of the health-care plan will likely curb the ambition of the tax overhaul, for both political and reasons and because of their decision to use the filibuster-proof Senate budget reconciliation process.