Paul Callan is a CNN legal analyst, a former New York City homicide prosecutor and currently is of counsel at the New York law firm of Edelman & Edelman PC , focusing on wrongful conviction and civil rights cases. Follow him on Twitter @paulcallan. The opinions expressed in this commentary are his own.

(CNN) What's gotten into Chuck Schumer? Throughout his Congressional career, the New York Democrat who's now the Senate minority leader has been a pragmatic liberal willing to work with colleagues on both sides of the legislative aisle.

On St. Patrick's Day, conservative Republican Congressman Peter King warmly introduced Schumer at New York's Friendly Sons of St. Patrick dinner as a fighter for New York on issues relating to homeland security.

King suggested that by the time Schumer finished his speech, many in the relatively conservative audience of 1,200 tuxedoed, mostly Irish-American men (and one woman: the Irish ambassador), would believe Sen. Schumer to be Irish.

After Schumer, whose ancestors came from Eastern Europe, quite far from the Emerald Isle, harvested warm laughter with self-deprecating humor and stories of his humble Brooklyn roots, King's remarks proved to be right on the mark.

Schumer's Gorsuch opposition strategy

Many in New York who have watched Schumer progress to his current position of power and influence are mystified that this pragmatic politician would lead a Supreme Court confirmation opposition battle that will most likely result in a loss and the destruction of the Senate's long-honored tradition of filibuster.

With a gusto matching Teddy Roosevelt's approach to San Juan Hill, the senator is rallying his Democratic troops to fight the Gorsuch nomination using the filibuster weapon, a weapon they are likely to need in future Supreme Court battles.

Republicans say their response will be to invoke the "nuclear option," a parliamentary maneuver utilized by former Democratic Senate Majority leader Harry Reid of Nevada to foil Republican efforts to block President Obama's nominees to the federal courts and other offices.

In November 2013, Reid and his Democratic allies held a majority in the Senate -- but not the three-fifths (60 votes) needed to close debate. Using a parliamentary maneuver that Republican Senator Trent Lott of Mississippi considered but abandoned, the Democrats proceeded by a simple majority vote to "blow up" the filibuster as it applied to nominations other than those to the Supreme Court.

With the same majority, they proceeded to approve President Obama's log-jammed nominees. They did this despite ominous warnings that the chickens would come home to roost if the Republicans ever achieved a Senate majority because the same maneuver could also be used against a Democratic minority.

Gorsuch widely seen as well qualified

The prophecy will come true if, as expected, the Gorsuch nomination is approved later this week by a slim majority vote of the Senate. Gorsuch is widely viewed as an exceptionally bright and well qualified nominee to fill the seat of the now deceased conservative justice, Antonin Scalia.

Though Democrats are claiming that he is "out of the mainstream," Gorsuch has routinely joined his liberal judicial colleagues in unanimous decisions where he says the law is clear. He is a self-described textualist with an extensive judicial history of conservative decisions but none that could be legitimately described as "nutty" or "extreme."

Like most judges, he makes occasional errors but nothing suggests a pattern of impropriety. Perhaps most importantly, his confirmation will not alter the current ideological composition of the court since he is a conservative replacing a conservative.

Why Schumer is provoking the nuclear option

The real mystery is why Schumer would provoke the nuclear option, forfeiting the remaining shreds of the filibuster in a fight he likely cannot win. He will really need the filibuster on the next nomination, which may involve filling the seat of a retiring liberal like Justice Ruth Bader Ginsburg or the court's swing vote, Justice Anthony Kennedy.

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Schumer has not lost his mind or his pragmatic streak.

Nor is he folding under pressure from the Democrats' "progressive" left wing. The Senate majority leader is preparing for the midterm elections in November of 2018, when 34 Senate seats are up for grabs.

In the fallout from the nuclear option and the Gorsuch confirmation, the strategic Schumer will criss-cross the country raising barrels of cash by reminding the Democratic base that without the protection of the filibuster, the party will be defenseless against the Republican Senate majority.

He will raise the specter of the evil Donald Trump packing the court with heartless conservatives who will crush progressive initiatives for the next 20 years. He will urge the wealthiest members of the Democratic base to give early and give often to avoid Trump Armageddon.

In the end, if Schumer plays the nuclear option correctly, he may turn potential disaster into his opportunity to become the most powerful and influential Senate majority leader since Lyndon Johnson.