Is Bryan Cranston the best American actor currently at work? It’s a silly question, of course: actors are not golfers who can be ranked by tournament victories and box-office takings. It is nonetheless hard to avoid the sense that, especially after the death of Philip Seymour Hoffman, Cranston occupies a space of his own.

That impression is greatly strengthened by seeing him tested on the Broadway stage in the hugely demanding central role of Lyndon Baines Johnson in Richard Schenkkan's All the Way , a quasi-documentary account of the year between John F Kennedy's assassination, in 1963, and Johnson's election as president in his own right, in 1964. The play has many parallels with Steven Spielberg's film Lincoln : black civil rights, the machinations of legislative change, and the ambiguous morality of achieving great ends by decidedly inglorious means. As such it invites comparison of Cranston's embodiment of a conflicted president with Daniel Day-Lewis's breathtaking Abraham Lincoln. It says much that Cranston is not at all diminished by the equation.

The role of LBJ is challenging in the usual ways that epic performances have to be: Cranston has to carry the dramatic weight of a complicated story and is on stage for most of the three hours of All the Way . Schenkkan's text is superbly structured and strikes an impressive balance between honouring the complexity of the story and shaping it into a compelling theatrical narrative. He cleverly parallels the politics of getting the Civil Rights Act through Congress with those of the civil-rights movement and Martin Luther King's need to hold together his increasingly fractious coalition. Bill Rauch's production matches that fluidity with its own pace and clarity and an excellent ensemble. But text and production stand or fall on Cranston's performance. And because of it they stand very tall indeed.

Cranston has to deal with two particular difficulties in playing LBJ, one apparently banal, the other more profound. The banal one is physical. Oddly enough, Johnson was the same height as Lincoln, at 6ft 4in. Day-Lewis, who is well over 6ft, had the advantage of a stovepipe hat and the tricks of the camera. Cranston, who is well under 6ft, has help from neither source. And, banal as this may be, it matters dramatically.

Johnson’s height was crucial to his political persona: in public as the big Texan lunk and in private as the figure who could intimidate others by looming over them. Cranston’s most immediate triumph is that on stage he is, indeed, 6ft 4in. He does it with his limbs, making them loose and lanky but also, extraordinarily, with his face. Strange as it may seem, his high forehead and pinched jaw make his face so long that you believe this must be the face of a very tall man.

We know from the brilliant knockabout of Malcolm in the Middle and the rawness of Breaking Bad that Cranston can act with his body, but doing it on stage is much more of a high-wire act. The writing and the production make much of LBJ's bodily presence. The way he physically addresses those he needs to seduce or bully is as important as what he says: now lover, now thug, now buttoned-up leader, now clown. LBJ deploys his body as he deploys everything else: as an instrument of power. Cranston infuses his own movements with that mesmerism and menace.

The other great challenge is the sheer complexity of the character. Schenkkan, following Robert Caro’s monumental biography, sees LBJ as a protagonist of almost Shakespearian ambiguity. Johnson is indeed unfathomable: a man who was often personally obnoxious, especially in his relations with women (his sexual behaviour makes the Kennedys look like Sting), he was responsible for more radically progressive legislation than any other 20th-century president apart from Franklin Roosevelt. He was the political creature of Big Oil and the Dixiecrats, but he truly hated poverty and dismantled Jim Crow. He was deeply vulgar and genuinely idealistic. He was a supremely gifted politicial tactician yet marched ever deeper into the swamp of Vietnam.

Again we know from Walter White's seamless transitions from good to evil and back again that Cranston can do complexity. It is one thing to do it in the wide spaces of a long TV serial; it is quite another to compress it into three hours on a stage. And not just to compress it but at the same time to leave it open, to avoid the temptation to resolve the contradictions. It would be very easy to let the vulgarity destroy the idealism or to allow the idealism to sentimentalise the ruthlessness. Cranston never does either. As well as using his body and brain, he uses his nerve, holding it all the way through by withholding any easy suggestion of where the "real" LBJ lies. It makes for a performance of rare power. It also has the makings of a great TV series: the second part of Schenkkan's LBJ cycle, The Great Society , opens in Oregon in July.

If it goes on like this, 1960s politics could be the new crystal meth.

All the Way is at the Neil Simon Theatre, New York, until June 29th

fotoole@irishtimes.com