Is there any legal obligation for the POTUS to stay sober? Obviously there is a moral obligation for the president to stay sober. However, is there any law that ensures this is the case?
Well, moral obligations are not laws, nor sometimes even moral obligations. Some laws are based on what some courts and legislatures think are moral obligations. We think cannibals have a moral obligation not to eat people; cannibals think non-cannibals are fools for passing up a good BBQ. As for a leader's moral responsibility for millions of lives, we can take as extreme examples Mao, Hilter, Stalin, Pol Pot, etc., that there are no obligations. The law that could apply in the case of a POTUS who does not "faithfully execute the Office of President of the United States..." (oath of office for POTUS) is that of "High Crimes and Misdemeanors", the grounds for most impeachments. But "faithfully executing the Office of President" has no moral obligation; it has legal implications, that's all. High crimes or misdemeanor are legal definitions, not moral, and depend on previous cases of what a crime or misdemeanor is. Insobriety can be illegal; there are laws on the books concerning public drunkenness. But in the contest of POTUS (one who is hopefully not passed out on the sidewalk in front of the WH), it remains to be seen if insobriety is a high crime or misdemeanor. That would be up to the House Judiciary Committee and US House of Representatives, which by Constitutional powers handles impeachment proceedings. The Twenty-fifth Amendment outlines who succeeds the president due to "Inability to discharge the Powers and Duties of the said Office," but it does not state who has the power to declare a President incapacitated. It's possible that a POTUS who incapacitates himself with alcohol is guilty of a "high crime or misdemeanor." But how drunk do you have to be to be incapacitated? Drunk enough to think a Game Boy is the nuclear football? Again, that's up to the House. Some past presidents have arguably been functional alcoholics (or functional recovered alcoholics.) But incapacitated? That can be subjective when it comes to the application of the law. And morals have little to do with it, unless those morals have a basis in that same law. Update 12/04/16: Some federal judges have been impeached due to drunkenness: http://www.fjc.gov/history/home.nsf/page/judges_impeachments.html and http://www.crf-usa.org/impeachment/high-crimes-and-misdemeanors.html
Political speech is at the core of First Amendment protections on free speech, but there are still legal limits that exist on political speech. (I respectfully disagree with the idea posited by user6726's good answer that political speech is immune from legal restraint.) Direct incitement to imminent lawless action that is likely to occur can technically be prohibited and people can be arrested for it, but the segments I've seen of the most pro-violence of Donald Trump's rallies have not quite risen to that standard. He has been couching his incitement-related language carefully; it sounds much tougher than it actually is. "I will pay to defend you if you commit a crime" or even an approving "back in the day, you used to get a punch in the face for X" is not the same as saying "Punch those people in the face on your way out" or "Let's knock those protestors out of here in 3, 2, 1... GO!" While I'm not saying that a pre-crime promise to cover legal fees can never be enough to rise to the level of conspiracy (that's an interesting question), it also isn't really incitement to riot. But If Donald Trump, or anyone else, used their political position to speak at a public event and directly incite a riot, then they could be arrested under an applicable law without violating the First Amendment. There are also other limits on political speech, such as defamation. While a political speaker has incredibly wide leeway, there are still limits that exist, especially if the speaker targets a private citizen rather than another political figure.
There is a saying that you can't sue city hall: that is applicable here. Governments enjoy sovereign immunity, and cannot be sued for their errors of judgment unless they specifically allow it. Safety regulations are an example of a situation where the government hold all of the power and shoulders none of the responsibility. If a government forbids sale or use of a substance on some grounds (could be safety, could be economic impact, could be something about preventing the moral decay of society), and the grounds later turns to be false, you cannot sue the government because of lost business opportunities. Generally speaking, that which is not prohibited is allowed, so there would have to be an affirmative duty for the government to prevent all forms of harm. If there were such a legal duty, there is a miniscule legal foundation for suing the government for shirking its duty. That is not a completely hypothetical possibility, in that the state of Washington imposes a constitutional duty on the legislature to provide public education, and the Supreme Court has done things to enforce this duty (the contempt of court fines are up in the realm of $80 million). Since there is no jurisdiction that imposes a duty on the government to absolutely prevent all harm, you won't be able to sue the government if they fail to outlaw a thing that is eventually proven to harm someone.
Generally, no. Legislatures pass laws. The fact that someone else knows more about the thing they're passing laws about is utterly irrelevant -- the power to make laws is given to the legislature, not to experts. If the legislature thinks experts should make the rules on something, they can delegate (this is why the FDA approves medicine rather than Congress), but the legislature of a state generally has the power to pass any law that is not unconstitutional. Your analogy to paper money is a poor one: that's a federalism thing, not an expertise thing. Congress has established a system of paper money, and states can't interfere with that. It's not that the Fed thinks paper money is good, it's that Congress said paper money shall be a thing. That could stop a state from banning an FDA-approved drug; however, since marijuana is illegal under federal law, it would be odd to conclude that banning it at the state level as well is preempted. Legislators aren't inherently experts on anything (except being elected). That doesn't matter. They have the authority to pass laws, even if those laws directly go against the views of people who are recognized experts in the area. You appear to think there must be a judicial remedy against bad policy. You would be wrong. The role of the courts is not to decide what policies are good or bad; they are concerned only with what is legal. Deciding what policies are good or bad is a matter for the democratically elected representatives of the people, or for the people themselves in states with ballot questions. It is not the job of the courts.
The Twenty Second Amendment is quite clear on this: No person shall be elected to the office of the President more than twice In your question, the President has been elected twice - unless of course the President was actually the Vice President (or elsewhere in the line of succession) at the start of the first term, in which case theres other limits: and no person who has held the office of President, or acted as President, for more than two years of a term to which some other person was elected President shall be elected to the office of the President more than once. So, someone who has held the office of President after being elevated to it rather than elected to it, but served no more than 1 year 364 days of that first term, could possibly, by the wording of the Twenty Second Amendment, be eligible to resign within their second term and stand again but only once more.
There is no parallelism between the Texas decision and the proposed lawsuit. In the anti-mifepristone lawsuit, there exists a statute granting the FDA authority to regulate and review new drugs, and a petition procedure whereby citizens can state ground for the Commissioner of Food and Drugs to consider a regulatory action. There is no statutory basis on which a ban of meat-eating could be created by executive action. Congress cannot be sued for not passing a law (failure or refusal of Congress to pass a particular law is not justiciable). If, for example someone were to submit a petition to the FDA urging such a regulation, the petition would have to be denied because the FDA does not have statutory authority to issue such a regulation. As argued here, the anti-mifepristone plaintiffs lack standing in that case, so one can expect that to be a substantial issue in the subsequent appeal.
There is no law governing the 'number' of the president. Common sense suggests that a person can't be 45th and 46th; there must be someone in between having the presidency and they will become the 46th president. In the extremely unlikely scenario that a foreign power occupies the United States this year, eliminates the office of President, and a few years later the US is liberated and Donald Trump is re-elected, I guess people could name him the 45th and 46th President, but it makes no sense to speculate about this.
Here are the Washington state proclamations with legal force, for example this proclamation amending proclamation 20-05. The legal authority is the paragraph starying &quot;NOW, THEREFORE, I, Jay Inslee, Governor of the state of Washington&quot; and what follows is what is legally proclaimed, in this case the effect is to &quot;waive and suspend portions of Title 79 RCW that require in-person meetings&quot;, pertaining to Dep't. of Natural Resources. Here is 20-25, the original stay-home proclamation. It claims Chapters 38.08, 38.52 and 43.06 RCW as authority, and prohibit[s] all people in Washington State from leaving their homes or participating in social, spiritual and recreational gatherings of any kind regardless of the number of participants, and all non-essential businesses in Washington State from conducting business, within the limitations provided herein. 43.06.220 is the main hammer that the governor can wield. The powers granted by the legislature include: (1) The governor after proclaiming a state of emergency and prior to terminating such, may, in the area described by the proclamation issue an order prohibiting: (a) Any person being on the public streets, or in the public parks, or at any other public place during the hours declared by the governor to be a period of curfew; (b) Any number of persons, as designated by the governor, from assembling or gathering on the public streets, parks, or other open areas of this state, either public or private; (c) The manufacture, transfer, use, possession or transportation of a molotov cocktail or any other device, instrument or object designed to explode or produce uncontained combustion; (d) The transporting, possessing or using of gasoline, kerosene, or combustible, flammable, or explosive liquids or materials in a glass or uncapped container of any kind except in connection with the normal operation of motor vehicles, normal home use or legitimate commercial use; (e) The sale, purchase or dispensing of alcoholic beverages; (f) The sale, purchase or dispensing of other commodities or goods, as he or she reasonably believes should be prohibited to help preserve and maintain life, health, property or the public peace; (g) The use of certain streets, highways or public ways by the public; and (h) Such other activities as he or she reasonably believes should be prohibited to help preserve and maintain life, health, property or the public peace. One could argue that some order is not reasonable, and perhaps it would fail strict scrutiny, if anyone sued. At present, though, there is no legal order. There is a guidance, a statement of best practices. There may well be a formal proclamation on this topic, which would wrap this in the legalities of other official proclamations. It boils down to RCW 43.06.220(1)(h).