(FORTUNE Magazine) – NOW THAT Rupert Murdoch is nearly maximally leveraged, the U.S. is under siege by another powerhouse press lord with the same monogram: Robert Maxwell. In November he won Macmillan, the staid but profitable textbook house, after a bloody brawl with management. Dubbed ''the bouncing Czech'' for his ability to rebound from setbacks, the Czechoslovakian-born entrepreneur, 65, had tried repeatedly to acquire a major publisher. Along the way he picked up some $500 million of U.S. printing companies, becoming second in that industry only to R.R. Donnelley. The Macmillan takeover brought him a step closer to realizing his dream of transforming Maxwell Communication -- a British media giant with 1987 profits of $220 million on revenues of $1.6 billion -- into one of the world's top communications conglomerates by 1990. He grandly forecasts ''revenues of at least $5.5 billion and profit growth to match.'' Though he's got a way to go, thinking big has always characterized Robert Maxwell. When he proposed to his bride in 1944 he promised: ''I shall win a Military Cross. I shall recreate a family. I shall make my fortune. I shall be Prime Minister of England. And I shall make you happy until the end of my days.'' So far, he's at least 3 for 5. Following World War II, a dashing young officer, born Ludvik Hoch, left the British Army with a Military Cross for bravery, the rank of captain, and a new name, Ian Robert Maxwell. In 1951 he borrowed money from relatives and bought controlling interest in a publisher of scientific and technical journals that he renamed Pergamon Press. He lost the company in 1969 when he was accused of grossly inflating its projected profits and British authorities branded him ''unfit to exercise proper stewardship of a public company.'' Eventually he regained control of Pergamon and took it private. Revealing the spit-in-your- eye swagger that marks many of his dealings, Maxwell transferred ownership in 1982 to a charitable foundation in Liechtenstein, about which he says little. According to his authorized biography, published this year, the foundation will help find a cure for AIDS, bring peace to the Middle East, eliminate racial hatred, and support ''charitable institutions in Liechtenstein.'' Maxwell can be warm or callous, as the situation demands. He once prefaced a wartime letter to his wife with ''I had a very amusing day yesterday,'' going on to describe how he had shot a town's mayor. Maxwell likes making snap decisions -- then reversing them. As a union leader says of him: ''He could charm the birds out of the trees, then shoot them.'' He fired his son Ian for being late to meet him at Orly Airport, only to rehire him later. Almost two years ago he launched, with much fanfare, a 24-hour newspaper called the London Daily News, which he said would capture half a million readers. Five months later he closed it, prompting such jokes as: ''Did you hear Cap'n Bob closed his 24-hour newspaper?'' ''No, how long did it last?'' ''Twenty-four hours.'' His zest for new projects continues undiminished. In December he introduced a test issue of a new daily, the European, which he hopes will become the USA Today of Europe. Projected circulation: half a million readers.

If Maxwell sounds like a man with a giant ego, he is. The Economist, reviewing his 525-page approved biography, noted that its photo section shows him ''with almost every dignitary known to man,'' including Princess Diana, Elton John, and the head of the People's Republic of Outer Mongolia. For some time, Mrs. Maxwell has been compiling books of clippings about her husband's doings. In a good year one comes in at around 60 pounds. When Maxwell's Daily Mirror (to which he contributes editorials under the pen name Charles Wilberforce) runs a bingo contest, the lucky winners are photographed against him as a backdrop. Such bumptiousness does not go down well in England, where the Queen reportedly has named her noisy spaniel Maxwell. How well he will be received in the U.S., where everyone expects to be famous for 15 minutes, is hard to say. But chances are, as Americans become better acquainted with him, they will come to share the view of a former Maxwell executive who said, in a reflective moment: ''You know, I find it increasingly difficult to dislike Bob Maxwell.'' A.F.