May 2025 – Two lower courts rule that President Trump’s sweeping tariffs exceed the authority granted by the International Emergency Economic Powers Act (IEEPA), setting the legal foundation for the Supreme Court challenge [3].

August 2025 – A federal appeals court affirms the lower‑court decision, confirming that the IEEPA‑based tariffs surpass presidential power and heightening the stakes of the pending Supreme Court review [11].

September 2025 – The Supreme Court agrees to hear the case, fast‑tracking the docket to address the administration’s claim that “time is of the essence” for the tariff program [2].

Nov 5 2025 – Oral arguments take place; justices split along ideological lines over the limits of executive authority under IEEPA, with several expressing skepticism about the White House’s justification [6].

Dec 3 2025 – Trump posts on Truth Social that the tariff case is “life or death” for the country and urges the Court to uphold the tariffs as essential for national security and economic stability [8].

Dec 4 2025 – Treasury Secretary Scott Bessent announces a backup tariff strategy that could replicate the current duties using Sections 301, 232 and 122 of trade law if the Court invalidates the IEEPA tariffs [7].

Dec 9 2025 – Trump warns that a ruling against his tariffs would be “the biggest threat in history” to U.S. national security, describing opponents as “dark and sinister forces” and stressing the policy’s role in strengthening the economy [6][21].

Jan 2 2026 – Trump tweets that losing the ability to impose tariffs would be a “terrible blow” to the United States, framing the tariffs as an unprecedented national benefit [20].

Jan 9 2026 – The Supreme Court postpones its decision, leaving the 15 % reciprocal tariff on Korean goods in place and maintaining uncertainty for global trade partners [18].

Jan 12 2026 – Trump warns on social media that a Court ruling striking down the tariffs would create a “complete mess” and make refunding billions of dollars “almost impossible” [1][5].

Jan 14 2026 – The Court again delays issuing a ruling, signaling a public session but releasing opinions in three unrelated cases instead [17].

Jan 15 2026 – South Korean Trade Minister Yeo Han‑koo says Seoul will monitor the outcome, prepare an “optimal response,” and notes the ruling could go either way, reflecting a 50‑50 outlook [15][16].

Jan 16 2026 – Administration officials outline a contingency plan that could invoke Section 301 authority and a 150‑day, 15 % tariff window to replace the IEEPA tariffs if needed [4].

Jan 19 2026 – USTR Jamieson Greer tells The New York Times the administration would reconstitute reciprocal tariffs the day after a adverse ruling, underscoring readiness to continue the policy [14].

Jan 20 2026 – Trump says he anxiously awaits the Court’s decision, warning that refunds could take years and stressing the tariffs’ importance for national security and revenue [11][13].

Jan 20 2026 – The Supreme Court again issues no opinion; the 15 % Korean tariff remains, and the August appellate ruling continues to shape expectations [13].

Jan 20 2026 – Treasury Secretary Bessent projects that the tariffs could generate up to $1 trillion for the Treasury by June if the Court allows them to stand [2].

Jan 20 2026 – Legal analysts note that the Court’s typical opinion‑release window falls around late February, suggesting a decision could arrive by Feb 20 2026 [2].

Jan 28 2026 – The Court confirms that justices are on recess and that opinions may be released on Feb 20, the usual deadline for the Court’s annual opinion cycle [2].

Jan 29 2026 – In a Cabinet meeting, Trump declares the current tariffs “already steep” and warns they could become “much steeper,” reiterating their role in national security and revenue generation [10].

Feb 20 2026 (anticipated) – The Supreme Court is expected to issue its opinion on the IEEPA tariff case, a decision that could reshape U.S. trade policy and determine whether backup statutory tools will be deployed [2].