For several years, the composition of the American Supreme Court has been a contentious partisan issue, generally simmering on the political stove but on several occasions boiling over into a full-blown pitched battle between conservative Republicans and liberal Democrats.

Senate GOP Majority Leader Mitch McConnell of Kentucky demonstrated skill and dogged determination in 2016 by frustrating Barack Obama’s attempt to nominate centrist judge Merrick Garland to fill the sudden vacancy created by the death of Antonin Scalia, a staunch conservative. McConnell still claims this triumph as among his greatest accomplishments.

After Donald Trump won the presidency in November 2016, he and McConnell proclaimed as one of their first orders of business the nomination and Senate confirmation of a similarly conservative judge to replace Scalia to cement the 5-4 right-leaning majority on the court. Neil Gorsuch is the result. Then Anthony Kennedy retired last summer and Trump and the Senate Republicans pushed through the fractious confirmation of Brett Kavanaugh to replace Kennedy.

Now these two new conservative justices, together with Clarence Thomas, Samuel Alito and Chief Justice John Roberts, form a putative 5-4 conservative majority.

We are about to see how that presumed balance functions in tense, highly-charged political times. The American high court may be in line to hear two significant cases and rule on them by this June. Both are likely to have lasting effects on the American political landscape, to say nothing of precedential interpretation of the separation of powers provided by the US constitution.

The first of these issues arises from Trump’s insistence on a southern border wall. While many pundits believe he is making a potentially fatal error in clinging to a concept that seems widely unpopular and a poor basis for the bitter election campaign to come next year, Trump has shown an impressive ability to pick an issue and stick to it. It’s why his supporters stick with him.

After last month’s disastrous US government shutdown for which Trump was appropriately blamed, there was no repeat last week, but there was also no congressional wall funding. Trump has now declared a state of emergency along the southern American border and aims to shift funds needed for his wall from other congressionally approved monies. He cites as his authority the National Emergencies Act of 1976, which has been cited in 58 less controversial cases since then without any intervention by the high US court.

Trump’s action appears to be contrary to a clause in Article 1 of the US constitution which states that “no money shall be withdrawn from the Treasury but in consequences of appropriations made by law.” This clause is also known as the power of the purse, and both Democratic and Republican presidents have been steadily chipping away at this concept for more than a generation.

Legal challenges to Trump’s assertion have already been promised by the American Civil Liberties Union and the State of California. A lawsuit has already been filed in Washington on behalf of Texas border landowners whose property would be seized for Trump’s wall - and who rely on temporary border-crossing workers to sustain their economic enterprises. Environmentally-based lawsuits may also emerge.

Outrage over Trump’s action is predictably building among Democrats and liberals. Murmuring is also audible from traditional conservatives and the many who protest any deviation from a strict interpretation of the American constitution.

While the Supreme Court faces the potential of a major separation of powers case to review this spring, it also accepted on Friday a case that challenges Commerce Secretary Wilbur Ross’s decision to add to the 2020 census questionnaire sent to all American households a question about citizenship of those residing in that household. Most observers agree the citizenship question is designed to discourage minority households from responding, which could diminish their share of congressional representation and access to federal funding.

New York District Judge Jesse Furman ruled recently that Ross’s action, which overruled his own department’s census experts, violated “a veritable smorgasbord” of federal rules, and blocked Commerce and Ross from further action as census preparation deadlines loom.

Rulings on the census and perhaps Trump’s wall could come by June. They will likely change American history. Stay tuned.