President Trump was understandably thrilled by the House’s passage of its tax-cut bill Thursday. On Twitter he called the vote a “a big step toward fulfilling our promise to deliver historic TAX CUTS for the American people by the end of the year.” Trump did not celebrate in the Rose Garden with House Republicans though, as he did following their passage of an Obamacare repeal bill in May. That victory lap on health care looked odd several weeks later, when the Senate failed to pass its version—and if the administration has learned anything from the Obamacare debacle, it’s to not declare a win too soon.

Once again, the Senate poses a problem for the White House’s legislative agenda. The votes