According to "Robert Maxwell Israel's Superspy"  by Gordon Thomas and Martin Dillon, Tower became the liaison for Robert Maxwell, a British publishing mogul and super-agent for Mossad, to the White House and to US government operations.
The relationship began in 1984, and the soon-to-be retired Tower "told Maxwell that his fee as Maxwell's personal consultant would be $200,000."
Tower received his fee in 4 separate payments of $50,000 into a Swiss bank account.
Tower arranged for Maxwell to meet with leadership of Sandia National Laboratories, a US nuclear lab.
Maxwell sold to Sandia a copy of PROMIS software that had a backdoor to Israeli Intelligence, giving nuclear details to Israel.
Shortly after retirement from the Senate, in 1985, Tower took Maxwell's request for American help in arming Iran, and relayed to President Reagan as a means to trade for American hostages held in Lebanon. "
Two days later the former Senator reported to Maxwell that his meeting with President Reagan had produced a positive response."

Tower retired from the Senate after nearly twenty-four years in office.
He continued to be involved in national politics, advising the campaigns of Ronald Reagan and George H. W. Bush.
Two weeks after his leaving office, Tower was named chief United States negotiator at the Strategic Arms Reduction Talks in Geneva, Switzerland.
Tower resigned from this office in 1987, and for a time was a professor at Southern Methodist University.
He became a consultant with Tower, Eggers, and Greene Consulting from 1987 until his death in 1991.

In November 1986, President Reagan asked Tower to chair the President's Special Review Board to study the action of the National Security Council and its staff during the Iran-Contra Affair.
The board, which became known as the Tower Commission, issued its report on February 26, 1987.
The report was highly critical of the Reagan administration and of the National Security Council's dealings with both Iran and the Nicaraguan Contras.

In 1989, Tower was President George H. W. Bush's choice to become Secretary of Defense.
In a stunning move, particularly since Tower was himself a former Senate colleague, the Senate rejected his nomination.
The largest factors were concern about possible conflicts of interest and Tower's personal life, in particular allegations of alcohol abuse and womanizing.
The Senate vote was 47–53, and it marked the first time that the Senate had rejected a Cabinet nominee of a newly elected president.

As The New York Times reported in his obituary, "Mr. Tower's repudiation by his former colleagues, who rejected him as President Bush's nominee for Secretary of Defense after public allegations of womanizing and heavy drinking, left a bitterness that could not be assuaged.
In the normally clubby Senate, Mr. Tower was regarded by some colleagues as a gut fighter who did not suffer fools gladly, and some lawmakers indicated that they were only too pleased to rebuke him."

In response to the alcohol allegations, Tower told The New York Times in 1990: "Have I ever drunk to excess?
Yes.
Am I alcohol-dependent?
No.
Have I always been a good boy?
Of course not.
But I've never done anything disqualifying.
That's the point."

After Tower's defeat, he was named chairman of the President's Foreign Intelligence Advisory Board.
Dick Cheney, then a Representative from Wyoming and the House Minority Whip, was later confirmed as Secretary of Defense.
According to "Robert Maxwell Israel's Superspy"  by Gordon Thomas and Martin Dillon, Tower became the liaison for Robert Maxwell, a British publishing mogul and super-agent for Mossad, to the White House and to US government operations. The relationship began in 1984, and the soon-to-be retired Tower "told Maxwell that his fee as Maxwell's personal consultant would be $200,000." Tower received his fee in 4 separate payments of $50,000 into a Swiss bank account. Tower arranged for Maxwell to meet with leadership of Sandia National Laboratories, a US nuclear lab. Maxwell sold to Sandia a copy of PROMIS software that had a backdoor to Israeli Intelligence, giving nuclear details to Israel. Shortly after retirement from the Senate, in 1985, Tower took Maxwell's request for American help in arming Iran, and relayed to President Reagan as a means to trade for American hostages held in Lebanon. "Two days later the former Senator reported to Maxwell that his meeting with President Reagan had produced a positive response."
Tower retired from the Senate after nearly twenty-four years in office. He continued to be involved in national politics, advising the campaigns of Ronald Reagan and George H. W. Bush. Two weeks after his leaving office, Tower was named chief United States negotiator at the Strategic Arms Reduction Talks in Geneva, Switzerland. Tower resigned from this office in 1987, and for a time was a professor at Southern Methodist University. He became a consultant with Tower, Eggers, and Greene Consulting from 1987 until his death in 1991.
In November 1986, President Reagan asked Tower to chair the President's Special Review Board to study the action of the National Security Council and its staff during the Iran-Contra Affair. The board, which became known as the Tower Commission, issued its report on February 26, 1987. The report was highly critical of the Reagan administration and of the National Security Council's dealings with both Iran and the Nicaraguan Contras.
In 1989, Tower was President George H. W. Bush's choice to become Secretary of Defense. In a stunning move, particularly since Tower was himself a former Senate colleague, the Senate rejected his nomination. The largest factors were concern about possible conflicts of interest and Tower's personal life, in particular allegations of alcohol abuse and womanizing. The Senate vote was 47–53, and it marked the first time that the Senate had rejected a Cabinet nominee of a newly elected president.
As The New York Times reported in his obituary, "Mr. Tower's repudiation by his former colleagues, who rejected him as President Bush's nominee for Secretary of Defense after public allegations of womanizing and heavy drinking, left a bitterness that could not be assuaged. In the normally clubby Senate, Mr. Tower was regarded by some colleagues as a gut fighter who did not suffer fools gladly, and some lawmakers indicated that they were only too pleased to rebuke him."
In response to the alcohol allegations, Tower told The New York Times in 1990: "Have I ever drunk to excess? Yes. Am I alcohol-dependent? No. Have I always been a good boy? Of course not. But I've never done anything disqualifying. That's the point."
After Tower's defeat, he was named chairman of the President's Foreign Intelligence Advisory Board. Dick Cheney, then a Representative from Wyoming and the House Minority Whip, was later confirmed as Secretary of Defense.
John Tower