For wealthy families, the underlying issue is straightforward, namely that a government carrying historic levels of debt, with rising costs of servicing it, will eventually have to confront the question of how to raise more revenue.

Any administration operating with limited room for additional borrowing and spending will have to consider its options, and private wealth, or taxing the income or private wealth of the rich as it will likely be put, will inevitably be part of that conversation.

Taxation is the obvious starting point. Federal decisions on income, capital gains, estate and gift taxes have a direct bearing on how wealth is held, invested and transferred between generations. The current federal estate and gift tax exemptions of $15m per individual, or $30m for married couples, provide considerable scope for planning. But assuming those thresholds, or the wider tax framework, will remain unchanged indefinitely would be a mistake.

For high-net-worth families, the real vulnerability is not simply whether a tax rate increases but whether the structures they have spent years putting in place will continue to work if the rules change. The time to examine those arrangements is before a legislative change makes the decision urgent.

Nor does diversifying wealth necessarily provide protection against these pressures. Many families spread capital across public equities, private equity, real estate, venture capital and international business interests. Whatever the investment merits of that approach, it does not create immunity from government policy. Different asset classes carry different tax treatments, reporting requirements and regulatory exposures. Changes to capital gains rules, the treatment of investment income or the taxation of particular structures can affect several parts of a portfolio at once.

In other words, diversification can spread investment risk without necessarily spreading tax risk. A portfolio that looks well balanced from an investment perspective may still be exposed to changes in the way governments choose to tax wealth.

State taxation adds another complication. Families with property, businesses or investments across multiple states can face very different obligations depending on where they live and how their affairs are organized, while the interaction between federal and state rules can make even apparently straightforward arrangements surprisingly complex.

For international families, the US system of citizenship-based taxation means American citizens often remain subject to US tax on worldwide income even when living abroad. Non-US families with American assets, business interests or beneficiaries may also find themselves caught by US tax and reporting requirements. Structures that work perfectly well under UK, European or Middle Eastern law can produce a very different result when assessed under the Internal Revenue Code.

The danger during periods of political and fiscal uncertainty is to react to individual headlines rather than consider the family’s overall position.

A more effective approach is to constantly review and adapt, if necessary, the entire wealth structure. Existing arrangements should be tested against a range of possible tax and regulatory scenarios, ranging from the plausible to the Black Swan type.

It also requires advisers to work together. Legal, tax and private wealth specialists need to understand the family’s wider objectives and the implications of decisions across different jurisdictions, as optimizing one part of a family’s affairs is of limited value if it creates an unexpected liability somewhere else.

This is not simply a defensive exercise. Families with well-organized and adaptable structures are better placed to respond to changes in the rules, make decisions calmly rather than under pressure, and choose where to establish businesses or hold assets. Flexibility is particularly valuable when the policy environment is ever changing.

The next two years may tell us more about the balance of power in Washington, but they are unlikely to resolve America’s underlying fiscal challenge. The pressure on government finances will remain, whichever party prevails.

Wealthy families should not wait for Washington to settle the debate before acting. The lesson of America’s fiscal position is not where to invest but when to plan: reviewing estate, trust and ownership structures while there is still time to do so calmly, rather than in the rush that follows a change in the law. The question is not which party wins the next election, but whether a family’s affairs are organized to adapt to whatever comes next.

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