The Supreme Court ruling barring judges from swiftly blocking government actions, even when they may be illegal, is yet another way that checks on executive authority have eroded as President Trump pushes to amass more power.

The decision on Friday, by a vote of 6 to 3, will allow Mr. Trump’s executive order seeking to end birthright citizenship to take effect in some parts of the country — even though every court that has looked at the directive has ruled it unconstitutional. That means some infants born to undocumented immigrants or foreign visitors without green cards can be denied citizenship-affirming documentation like Social Security numbers.

But the diminishing of judicial authority as a potential counterweight to exercises of presidential power carries implications far beyond the issue of citizenship. The Supreme Court is effectively tying the hands of lower-court judges at a time when they are trying to respond to a steady geyser of aggressive executive branch orders and policies.

The ability of district courts to swiftly block Trump administration actions from being enforced in the first place has acted as a rare effective check on his second-term presidency. But generally, the pace of the judicial process is slow and has struggled to keep up. Actions that already took place by the time a court rules them illegal, like shutting down an agency or sending migrants to a foreign prison without due process, can be difficult to unwind.

Presidential power historically goes through ebbs and flows, with fundamental implications for the functioning of the system of checks and balances that defines American-style democracy.

But it has generally been on an upward path since the middle of the 20th century. The growth of the administrative state inside the executive branch, and the large standing armies left in place as World War II segued into the Cold War, inaugurated what the historian Arthur Schlesinger Jr. coined the “imperial presidency.”