The Conservatives have promised to make fighting drugs the top priority in their tough line against crime.
Mr Davis plans to scrap Labour's early release scheme for prisoners
Shadow home secretary David Davis told the Tory party conference: "Some people say we have lost the war on drugs, I say we have not begun to fight it."
He is pledging to accelerate the start of random drug-testing of school pupils and bring a ten-fold increase in residential drug rehabilitation places.
Mr Davis also plans 20,000 extra prison places, declaring: "Prison works."
And he said he would substantially cut immigration numbers.
Under the Tory plans, drugs rehabilitation places would rise from 2,000 to 20,000.
Mr Davis said offering addicts the choice of undergoing
rehabilitation to escape prison - a plan unveiled last year - was "no soft option".
"It will mean court supervision, and failure will mean prison," he said, telling Tory activists there were now one million hard drug users in Britain.
Drugs in schools
A Sun newspaper survey suggested up to 100,000 children aged from 13 to 15 in
the UK have used cocaine, said Mr Davis.
"That is why we will
support, encourage and accelerate the implementation of random drug-testing of
"Children need to know that it is not cool to use drugs - it is
stupid, it is dangerous, it is illegal. And parents should know the law will be enforced."
Mr Davis said there would be a drugs epidemic with terrible effects on all society if nothing was done.
The Tories say they would restore the pension-earnings link
"I make no apology for taking a hard line on drugs," he said. "They destroy lives,
destroy society and render all our efforts to reduce crime worthless."
Under Labour "more and more people see the decent majority as another soft touch", he claimed.
People should be able to choose who ran their local police force and determine their priorities, he said.
He highlighted plans to recruit 40,000 extra police with paperwork cut and national targets scrapped.
Mr Davis reiterated plans to scrap Labour's early-release scheme for prisoners, claiming it had allowed 3,600 "needless crimes".
He attacked Labour for allowing a shortage of prison places which had dictated sentencing policies.
In an echo of Michael Howard when he was home secretary, he declared: "Prison does work, it is a deterrent and criminals fear it."
Electronic tagging had to be an addition to prison, not an alternative, he insisted.
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The Tories say they will create 20,000 more prison places, using £1m saved by reducing crime and ensuring proper rehabilitation schemes.
On immigration and asylum, Mr Davis branded the current system as "catastrophic and chaotic".
"Immigration alone could fill six cities the size of Birmingham over the next three decades.
He highlighted Tory plans for an annual immigration limit but insisted the party welcomed the contribution made by immigrants and suggested the quota for refugees could be higher than the number of asylum applications actually agreed at the moment.
Immigration would be a central issue at the next election, he added, warning that if the legitimate parties did not discuss it, extremists would.
Liberal Democrat home affairs spokesman Mark Oaten said Mr Davis had "blown apart" his leader's pledge only to make promises they could deliver. by making uncosted proposals.
Home Office Minister Hazel Blears said the Tories wanted to cut the Home Office budget by £1.6bn.
She asked: "How many police and community support officers will go? What will be cut from the investment in the protection of our borders?"
Also on Wednesday, shadow work and pensions secretary David Willetts has announced plans for a scheme called Work First to replace Labour's New Deal.
Charities and businesses would offer work placements and job-search services to help the unemployed find work, he said.
And the money saved would be used to restore the link between pensions and earnings with means testing reduced.
Mr Willetts also attacked Labour's record, saying a "shocking" 10,300 pension schemes had wound up since 1997.
Meanwhile, shadow defence secretary Nicholas Soames renewed promises to spend an extra £2.7bn on front line armed forces.
The move would reverse the disbandment of historic Scottish
regiments as part of a package of abandoning armed forces cuts planned by the government, he said.
On Tuesday, Mr Howard put trust centre stage in his first annual conference speech as party leader as he promised to sack ministers who failed to deliver.