It’s too early to blink, but the pressure is slowly beginning to rise.

The government shutdown drama is still in its opening act with Democrats and Republicans each heaping blame on the other side.

And despite deepening partisan bitterness in Washington, nothing has changed the equation that led to the impasse: Republicans and Democrats both saw a greater political advantage in letting the government close than in keeping it open.

But the earliest signs were evident Wednesday of the political strains that will eventually crack the unity of one or both parties — whether it takes days or weeks — and end the standoff.

Day One saw the rollout of initial battleground strategies:

The White House adopted a ruthless position, threatening mass firings of federal workers and halting billions of dollars in public funds to humiliate Democratic leaders.

Democrats, meanwhile, hammered their key claim that Trump will make health care more expensive for millions.

There were rumblings of behind-the-scenes discussions to end the shutdown in the Senate from key players in the ever-diminishing political center.

And some early signs of disquiet emerged among some important Republicans over Trump’s hardball tactics.

Still, this is a tough crisis to call, partly because America has a president who has a history of metaphorically blowing everything up one minute, then suddenly seeking a deal that can undermine the painstakingly laid plans of his own side