They said the convergence of events — as special counsel Robert Mueller probes whether Trump’s campaign colluded with Russia to tilt the 2016 election in his favor, and a soon-to-be Democrat-led House starts launching related investigations — made for highly precarious political waters.

The 44 include Democrats such as Bill Bradley and John Kerry and Republicans such as Ben Nighthorse Campbell and Richard Lugar, and they paint the situation ominously as a constitutional crisis.

“It is our shared view that we are entering a dangerous period, and we feel an obligation to speak up about serious challenges to the rule of law, the Constitution, our governing institutions and our national security,” the ex-lawmakers wrote in a Washington Post opinion piece Monday.

“We are at an inflection point in which the foundational principles of our democracy and our national security interests are at stake, and the rule of law and the ability of our institutions to function freely and independently must be upheld,” they wrote.

And “at other critical moments in our history, when constitutional crises have threatened our foundations, it has been the Senate that has stood in defense of our democracy. Today is once again such a time,” the group stressed.

They urged current and future members of the US Senate to make sure that “partisanship or self-interest not replace national interest.” Bipartisan cooperation has plunged with Trump in power.

How lawmakers in both houses of Congress handle the crisis will be key to how the nation handles Trump’s being its first sitting president implicated in a felony