The following is based on a comment I wrote on Facebook. I'm placing it here so it is more visible and more publicly archived for the benefit of society.
I disagree that legalizing illegal drugs condones an activity. Something being legal is the default state with regard to a any given activity. It is more or less a neutral state. When a new activity comes along, the default assumption is that it's acceptable, because we live in a society where individual liberty is ideally preserved at the expense of every other consideration except immediately deadly acts, ones that immediately threaten national security, and ones that destroy/infringe the integrity of others' property/person(I might be missing something).
It takes directed legal action to make something illegal.
Condoning an activity in society is when the government promotes or subsidizes an activity. This can be done by way of encouragement through communication or giving money to those who participate in the activity.
Marijuana activists are not asking for subsidies or promotion from the government. In fact, I'm quite sure most would accept government condemnation through strong regulation, anti-marijuana abuse education, and lots of taxes.
When you make an activity illegal, you actively commit society to remove people's liberty and punish those who participate in the activity. Marijuana being illegal is not a default inert state, where making it legal would condone the activity. It takes active funding of police action in government budgets every year to enforce the punishment of those who participate in this action through arrests, prosecution, fines, property confiscation, and jail time. You're removing people's liberty to do an activity that meets none of the requirements for an action that should be punished under the law.
This is why marijuana posession and consumption should be reverted to its default state of being neutrally legal, and condemned by the government in an appropriate way through regulation, education, and taxes.