That's been tried before with little success. Some people will choose to use drugs no matter what the government does. Some people will choose to be homeless. Some people are mentally ill and unable to take advantage of government programs. Some people just refuse help.
What program would you suggest, that isn't being done, that would reduce homelessness or drug overdose?
Just one of the 59 cruise missiles fired on Syria yesterday would fund intervening in and saving hundreds of lives - they cost $1.41 million each. Some people may refuse help, many, many people in these situations don't get help. Soup kitchens, treatment for mental illness, shelters, training, are all worthy causes which cost very little to run.
There are so many useful programs that could be funded, which are being defunded this year in order to prioritise spending on the military (already the largest in the world by some margin) and searching social accounts/mobile phones and storing passwords for who knows what reason (it certainly isn't to prevent terrorism).
Great success. Do some research. Spend effort expanding programs that work.
> Later, the Bush administration adopted the model, and cities and states started writing 10-year plans to end chronic homelessness.
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> And even though many cities in the U.S. have also been doing this for a while, they still come to Utah to study why it's working so well here.
The article mentions several times that it's already being done. This isn't mutually exclusive with efforts to fight terrorism.